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Class: ActiveRecord::ConnectionAdapters::AbstractAdapter

Relationships & Source Files
Namespace Children
Classes:
Extension / Inclusion / Inheritance Descendants
Subclasses:
Super Chains via Extension / Inclusion / Inheritance
Class Chain:
Instance Chain:
Inherits: Object
Defined in: activerecord/lib/active_record/connection_adapters/abstract_adapter.rb

Overview

Active Record Abstract Adapter

Active Record supports multiple database systems. AbstractAdapter and related classes form the abstraction layer which makes this possible. An AbstractAdapter represents a connection to a database, and provides an abstract interface for database-specific functionality such as establishing a connection, escaping values, building the right SQL fragments for :offset and :limit options, etc.

All the concrete database adapters follow the interface laid down in this class. {ActiveRecord::Base.lease_connection} returns an AbstractAdapter object, which you can use.

Most of the methods in the adapter are useful during migrations. Most notably, the instance methods provided by SchemaStatements are very useful.

Constant Summary

::ActiveSupport::Callbacks - Included

CALLBACK_FILTER_TYPES

DatabaseStatements - Included

DEFAULT_INSERT_VALUE, HIGH_PRECISION_CURRENT_TIMESTAMP, TRANSACTION_ISOLATION_LEVELS

::ActiveSupport::Callbacks - Attributes & Methods

Class Attribute Summary

Class Method Summary

Instance Attribute Summary

DatabaseStatements - Included

SchemaStatements - Included

Instance Method Summary

Savepoints - Included

DatabaseLimits - Included

#index_name_length

Returns the maximum length of an index name.

#table_alias_length

Returns the maximum length of a table alias.

#table_name_length

Returns the maximum length of a table name.

#bind_params_length, #max_identifier_length

Quoting - Included

#quote

Quotes the column value to help prevent SQL injection attacks.

#quote_column_name

Quotes the column name.

#quote_string

Quotes a string, escaping any ‘ (single quote) and \ (backslash) characters.

#quote_table_name

Quotes the table name.

#quote_table_name_for_assignment

Override to return the quoted table name for assignment.

#quoted_date

Quote date/time values for use in SQL input.

#quoted_false, #quoted_true,
#type_cast

Cast a value to a type that the database understands.

#unquoted_false, #unquoted_true,
#cast_bound_value

Cast a value to be used as a bound parameter of unknown type.

#lookup_cast_type, #quote_default_expression, #quoted_binary, #quoted_time, #sanitize_as_sql_comment, #type_casted_binds

DatabaseStatements - Included

#add_transaction_record

Register a record with the current transaction so that its after_commit and after_rollback callbacks can be called.

#begin_db_transaction

Begins the transaction (and turns off auto-committing).

#begin_isolated_db_transaction

Begins the transaction with the isolation level set.

#commit_db_transaction

Commits the transaction (and turns on auto-committing).

#create
#default_sequence_name,
#delete

Executes the delete statement and returns the number of rows affected.

#disable_lazy_transactions!, #empty_insert_statement_value, #enable_lazy_transactions!,
#exec_delete

Executes delete sql statement in the context of this connection using binds as the bind substitutes.

#exec_insert

Executes insert sql statement in the context of this connection using binds as the bind substitutes.

#exec_query

Executes sql statement in the context of this connection using binds as the bind substitutes.

#exec_update

Executes update sql statement in the context of this connection using binds as the bind substitutes.

#execute

Executes the SQL statement in the context of this connection and returns the raw result from the connection adapter.

#high_precision_current_timestamp

Returns an ::Arel SQL literal for the CURRENT_TIMESTAMP for usage with arbitrary precision date/time columns.

#initialize,
#insert

Executes an INSERT query and returns the new record’s ID.

#insert_fixture

Inserts the given fixture into the table.

#insert_fixtures_set,
#reset_isolation_level

Hook point called after an isolated DB transaction is committed or rolled back.

#reset_sequence!

Set the sequence to the max value of the table’s column.

#restart_db_transaction,
#rollback_db_transaction

Rolls back the transaction (and turns on auto-committing).

#rollback_to_savepoint,
#select_all

Returns an ::ActiveRecord::Result instance.

#select_one

Returns a record hash with the column names as keys and column values as values.

#select_rows

Returns an array of arrays containing the field values.

#select_value

Returns a single value from a record.

#select_values

Returns an array of the values of the first column in a select:

#to_sql

Converts an arel AST to SQL.

#transaction

Runs the given block in a database transaction, and returns the result of the block.

#transaction_isolation_levels,
#truncate

Executes the truncate statement.

#update

Executes the update statement and returns the number of rows affected.

#write_query?

Determines whether the SQL statement is a write query.

#affected_rows, #arel_from_relation, #build_delete_from_statements, #build_fixture_sql, #build_fixture_statements, #build_truncate_statement, #build_truncate_statements,
#cast_result

Receive a native adapter result object and returns an ::ActiveRecord::Result object.

#combine_multi_statements, #execute_batch, #extract_table_ref_from_insert_sql, #handle_warnings, #internal_build_intent, #last_inserted_id, #perform_query, #returning_column_values, #single_value_from_rows, #_exec_insert, #begin_deferred_transaction,
#cacheable_query

This is used in the ::ActiveRecord::StatementCache object.

#default_insert_value, #empty_all_tables, #exec_insert_all, #exec_restart_db_transaction, #exec_rollback_db_transaction,
#execute_intent

Lowest-level abstract execution of a query, called only from the intent itself.

#explain, #query_all, #query_command, #query_one, #query_rows, #query_value, #query_values, #reset_transaction, #to_sql_and_binds, #truncate_tables,
#with_yaml_fallback

::ActiveRecord::Fixture value is quoted by ::Arel, however scalar values are not quotable.

#sql_for_insert

SchemaStatements - Included

#add_belongs_to
#add_check_constraint

Adds a new check constraint to the table.

#add_column

Add a new type column named column_name to table_name.

#add_foreign_key

Adds a new foreign key.

#add_index

Adds a new index to the table.

#add_reference

Adds a reference.

#add_timestamps

Adds timestamps (created_at and updated_at) columns to table_name.

#assume_migrated_upto_version,
#build_create_table_definition

Returns a TableDefinition object containing information about the table that would be created if the same arguments were passed to #create_table.

#change_column

Changes the column’s definition according to the new options.

#change_column_comment

Changes the comment for a column or removes it if nil.

#change_column_default

Sets a new default value for a column:

#change_column_null

Sets or removes a NOT NULL constraint on a column.

#change_table

A block for changing columns in table.

#change_table_comment

Changes the comment for a table or removes it if nil.

#check_constraint_exists?

Checks to see if a check constraint exists on a table for a given check constraint definition.

#check_constraints

Returns an array of check constraints for the given table.

#column_exists?

Checks to see if a column exists in a given table.

#columns

Returns an array of Column objects for the table specified by table_name.

#create_join_table

Creates a new join table with the name created using the lexical order of the first two arguments.

#create_table

Creates a new table with the name table_name.

#data_source_exists?

Checks to see if the data source name exists on the database.

#data_sources

Returns the relation names usable to back Active Record models.

#disable_index

Prevents an index from being used by queries.

#drop_join_table

Drops the join table specified by the given arguments.

#drop_table

Drops a table or tables from the database.

#enable_index

Enables an index to be used by queries.

#foreign_key_exists?

Checks to see if a foreign key exists on a table for a given foreign key definition.

#foreign_keys

Returns an array of foreign keys for the given table.

#index_exists?

Checks to see if an index exists on a table for a given index definition.

#index_name_exists?

Verifies the existence of an index with a given name.

#indexes

Returns an array of indexes for the given table.

#max_index_name_size

Returns the maximum length of an index name in bytes.

#native_database_types

Returns a hash of mappings from the abstract data types to the native database types.

#options_include_default?,
#primary_key

Returns just a table’s primary key.

#remove_belongs_to
#remove_check_constraint

Removes the given check constraint from the table.

#remove_column

Removes the column from the table definition.

#remove_columns

Removes the given columns from the table definition.

#remove_foreign_key

Removes the given foreign key from the table.

#remove_index

Removes the given index from the table.

#remove_reference

Removes the reference(s).

#remove_timestamps

Removes the timestamp columns (created_at and updated_at) from the table definition.

#rename_column

Renames a column.

#rename_index

Renames an index.

#rename_table

Renames a table.

#table_alias_for

Truncates a table alias according to the limits of the current adapter.

#table_comment

Returns the table comment that’s stored in database metadata.

#table_exists?

Checks to see if the table table_name exists on the database.

#table_options,
#tables

Returns an array of table names defined in the database.

#view_exists?

Checks to see if the view view_name exists on the database.

#views

Returns an array of view names defined in the database.

#add_column_for_alter, #add_index_sort_order,
#add_options_for_index_columns

Overridden by the MySQL adapter for supporting index lengths and by the PostgreSQL adapter for supporting operator classes.

#add_timestamps_for_alter, #can_remove_index_by_name?, #change_column_default_for_alter, #check_constraint_for, #check_constraint_for!, #check_constraint_name, #column_options_keys, #create_alter_table, #create_index_definition, #create_table_definition, #data_source_sql,
#expression_column_name?

Try to identify whether the given column name is an expression.

#extract_foreign_key_action,
#extract_new_comment_value
#extract_new_default_value, #fetch_type_metadata, #foreign_key_for, #foreign_key_for!, #foreign_key_name, #generate_index_name, #index_column_names, #index_name_for_remove, #index_name_options, #insert_versions_sql, #options_for_index_columns, #quoted_scope, #reference_name_for_table, #remove_column_for_alter, #remove_columns_for_alter, #remove_timestamps_for_alter, #rename_column_indexes, #rename_column_sql, #rename_table_indexes, #strip_table_name_prefix_and_suffix, #valid_index_options, #validate_change_column_null_argument!, #validate_create_table_options!, #validate_index_length!, #validate_table_length!, #add_columns, #add_index_options,
#build_add_column_definition

Builds an AlterTable object for adding a column to a table.

#build_change_column_default_definition
#build_create_index_definition

Builds a CreateIndexDefinition object.

#build_create_join_table_definition

Builds a TableDefinition object for a join table.

#bulk_change_table, #check_constraint_options,
#columns_for_distinct

Given a set of columns and an ORDER BY clause, returns the columns for a SELECT DISTINCT.

#create_schema_dumper, #distinct_relation_for_primary_key, #dump_schema_versions, #foreign_key_column_for, #foreign_key_options, #index_algorithm, #index_name, #internal_string_options_for_primary_key, #quoted_columns_for_index, #remove_constraint,
#schema_creation

Returns an instance of SchemaCreation, which can be used to visit a schema definition object and return DDL.

#type_to_sql, #update_table_definition, #valid_column_definition_options, #valid_primary_key_options, #valid_table_definition_options

::ActiveRecord::Migration::JoinTable - Included

::ActiveSupport::Callbacks - Included

#run_callbacks

Runs the callbacks for the given event.

#halted_callback_hook

A hook invoked every time a before callback is halted.

Constructor Details

.new(config_or_deprecated_connection, deprecated_logger = nil, deprecated_connection_options = nil, deprecated_config = nil) ⇒ AbstractAdapter

This method is for internal use only.
[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 145

def initialize(config_or_deprecated_connection, deprecated_logger = nil, deprecated_connection_options = nil, deprecated_config = nil) # :nodoc:
  super()

  @raw_connection = nil
  @unconfigured_connection = nil
  @connected_since = nil

  if config_or_deprecated_connection.is_a?(Hash)
    @config = config_or_deprecated_connection.symbolize_keys
    @logger = ActiveRecord::Base.logger

    if deprecated_logger || deprecated_connection_options || deprecated_config
      raise ArgumentError, "when initializing an Active Record adapter with a config hash, that should be the only argument"
    end
  else
    # Soft-deprecated for now; we'll probably warn in future.

    @unconfigured_connection = config_or_deprecated_connection
    @connected_since = Process.clock_gettime(Process::CLOCK_MONOTONIC)
    @logger = deprecated_logger || ActiveRecord::Base.logger
    if deprecated_config
      @config = (deprecated_config || {}).symbolize_keys
      @connection_parameters = deprecated_connection_options
    else
      @config = (deprecated_connection_options || {}).symbolize_keys
      @connection_parameters = nil
    end
  end

  @owner = nil
  @pinned = false
  @pool = ActiveRecord::ConnectionAdapters::NullPool.new
  @idle_since = Process.clock_gettime(Process::CLOCK_MONOTONIC)
  @allow_preconnect = false
  @visitor = arel_visitor
  @statements = build_statement_pool
  self.lock_thread = nil

  @prepared_statements = !ActiveRecord.disable_prepared_statements && self.class.type_cast_config_to_boolean(
    @config.fetch(:prepared_statements) { default_prepared_statements }
  )

  @advisory_locks_enabled = self.class.type_cast_config_to_boolean(
    @config.fetch(:advisory_locks, true)
  )

  @default_timezone = self.class.validate_default_timezone(@config[:default_timezone])

  @raw_connection_dirty = false
  @last_activity = nil
  @verified = false

  @pool_jitter = rand * max_jitter
end

Class Attribute Details

.__callbacks (rw)

[ GitHub ]

  
# File 'activesupport/lib/active_support/callbacks.rb', line 70

class_attribute :__callbacks, instance_writer: false, instance_predicate: false, default: {}

.migration_strategy (rw)

Allows configuration of migration strategy per adapter type. When set on a specific adapter class (e.g., PostgreSQLAdapter), all migrations using that adapter will use the specified strategy instead of the global ActiveRecord.migration_strategy.

ActiveRecord::ConnectionAdapters::PostgreSQLAdapter.migration_strategy = CustomPostgresStrategy
ActiveRecord::ConnectionAdapters::Mysql2Adapter.migration_strategy = CustomMySQLStrategy
[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 44

class_attribute :migration_strategy, instance_writer: false

.migration_strategy?Boolean (rw)

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 44

class_attribute :migration_strategy, instance_writer: false

Class Method Details

.build_read_query_regexp(*parts)

This method is for internal use only.
[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 106

def self.build_read_query_regexp(*parts) # :nodoc:
  parts += DEFAULT_READ_QUERY
  parts = parts.map { |part| /#{part}/i }
  /\A(?:[(\s]|#{COMMENT_REGEX})*#{Regexp.union(*parts)}/
end

.database_exists?(config) ⇒ Boolean

Does the database for this adapter exist?

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 410

def self.database_exists?(config)
  new(config).database_exists?
end

.dbconsole(config, options = {})

Opens a database console session.

Raises:

  • (NotImplementedError)
[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 141

def self.dbconsole(config, options = {})
  raise NotImplementedError.new("#{self.class} should define `dbconsole` that accepts a db config and options to implement connecting to the db console")
end

.extended_type_map(default_timezone:)

This method is for internal use only.
[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 951

def extended_type_map(default_timezone:) # :nodoc:
  Type::TypeMap.new(self::TYPE_MAP).tap do |m|
    register_class_with_precision m, %r(\A[^\(]*time)i, Type::Time, timezone: default_timezone
    register_class_with_precision m, %r(\A[^\(]*datetime)i, Type::DateTime, timezone: default_timezone
    m.alias_type %r(\A[^\(]*timestamp)i, "datetime"
  end
end

.extract_limit(sql_type) (private)

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 1015

def extract_limit(sql_type)
  $1.to_i if sql_type =~ /\((.*)\)/
end

.extract_precision(sql_type) (private)

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 1011

def extract_precision(sql_type)
  $1.to_i if sql_type =~ /\((\d)(,\d)?\)/
end

.extract_scale(sql_type) (private)

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 1004

def extract_scale(sql_type)
  case sql_type
  when /\((\d+)\)/ then 0
  when /\((\d)(,(\d))\)/ then $3.to_i
  end
end

.find_cmd_and_exec(commands, *args)

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 112

def self.find_cmd_and_exec(commands, *args) # :doc:
  commands = Array(commands)

  dirs_on_path = ENV["PATH"].to_s.split(File::PATH_SEPARATOR)
  unless (ext = RbConfig::CONFIG["EXEEXT"]).empty?
    commands = commands.map { |cmd| "#{cmd}#{ext}" }
  end

  full_path_command = nil
  found = commands.detect do |cmd|
    dirs_on_path.detect do |path|
      full_path_command = File.join(path, cmd)
      begin
        stat = File.stat(full_path_command)
      rescue SystemCallError
      else
        stat.file? && stat.executable?
      end
    end
  end

  if found
    exec full_path_command, *args
  else
    abort("Couldn't find database client: #{commands.join(', ')}. Check your $PATH and try again.")
  end
end

.initialize_type_map(m) (private)

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 964

def initialize_type_map(m)
  register_class_with_limit m, %r(boolean)i,       Type::Boolean
  register_class_with_limit m, %r(char)i,          Type::String
  register_class_with_limit m, %r(binary)i,        Type::Binary
  register_class_with_limit m, %r(text)i,          Type::Text
  register_class_with_precision m, %r(date)i,      Type::Date
  register_class_with_precision m, %r(time)i,      Type::Time
  register_class_with_precision m, %r(datetime)i,  Type::DateTime
  register_class_with_limit m, %r(float)i,         Type::Float
  register_class_with_limit m, %r(int)i,           Type::Integer

  m.alias_type %r(blob)i,      "binary"
  m.alias_type %r(clob)i,      "text"
  m.alias_type %r(timestamp)i, "datetime"
  m.alias_type %r(numeric)i,   "decimal"
  m.alias_type %r(number)i,    "decimal"
  m.alias_type %r(double)i,    "float"

  m.register_type %r(^json)i, Type::Json.new.freeze

  m.register_type(%r(decimal)i) do |sql_type|
    scale = extract_scale(sql_type)
    precision = extract_precision(sql_type)

    if scale == 0
      # FIXME: Remove this class as well
      Type::DecimalWithoutScale.new(precision: precision).freeze
    else
      Type::Decimal.new(precision: precision, scale: scale).freeze
    end
  end
end

.register_class_with_limit(mapping, key, klass) (private)

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 997

def register_class_with_limit(mapping, key, klass)
  mapping.register_type(key) do |*args|
    limit = extract_limit(args.last)
    klass.new(limit: limit).freeze
  end
end

.register_class_with_precision(mapping, key, klass, **kwargs)

This method is for internal use only.
[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 944

def register_class_with_precision(mapping, key, klass, **kwargs) # :nodoc:
  mapping.register_type(key) do |*args|
    precision = extract_precision(args.last)
    klass.new(precision: precision, **kwargs).freeze
  end
end

.type_cast_config_to_boolean(config)

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 85

def self.type_cast_config_to_boolean(config)
  if config == "false"
    false
  else
    config
  end
end

.type_cast_config_to_integer(config)

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 75

def self.type_cast_config_to_integer(config)
  if config.is_a?(Integer)
    config
  elsif SIMPLE_INT.match?(config)
    config.to_i
  else
    config
  end
end

.valid_type?(type) ⇒ Boolean

This method is for internal use only.
[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 959

def valid_type?(type) # :nodoc:
  !native_database_types[type].nil?
end

.validate_default_timezone(config)

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 93

def self.validate_default_timezone(config)
  case config
  when nil
  when "utc", "local"
    config.to_sym
  else
    raise ArgumentError, "default_timezone must be either 'utc' or 'local'"
  end
end

Instance Attribute Details

#__callbacks (readonly)

[ GitHub ]

  
# File 'activesupport/lib/active_support/callbacks.rb', line 70

class_attribute :__callbacks, instance_writer: false, instance_predicate: false, default: {}

#active?Boolean (readonly)

Checks whether the connection to the database is still active. This includes checking whether the database is actually capable of responding, i.e. whether the connection isn’t stale.

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 712

def active?
end

#advisory_locks_enabled?Boolean (readonly)

This method is for internal use only.
[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 659

def advisory_locks_enabled? # :nodoc:
  supports_advisory_locks? && @advisory_locks_enabled
end

#allow_preconnect (rw)

This method is for internal use only.
[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 59

attr_reader :allow_preconnect # :nodoc:

#allow_preconnect=(value) (rw)

This method is for internal use only.
[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 69

def allow_preconnect=(value) # :nodoc:
  @lock.synchronize do
    @allow_preconnect = value
  end
end

#async_enabled?Boolean (readonly)

This method is for internal use only.
[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 618

def async_enabled? # :nodoc:
  supports_concurrent_connections? &&
    !ActiveRecord.async_query_executor.nil? && !pool.async_executor.nil?
end

#connected?Boolean (readonly)

Checks whether the connection to the database was established. This doesn’t include checking whether the database is actually capable of responding, i.e. whether the connection is stale.

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 705

def connected?
  !@raw_connection.nil?
end

#database_exists?Boolean (readonly)

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 414

def database_exists?
  connect!
  true
rescue ActiveRecord::NoDatabaseError
  false
end

#in_use? (readonly)

Alias for #owner.

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 61

alias :in_use? :owner

#lock (readonly)

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 58

attr_reader :visitor, :owner, :logger, :lock

#lock_thread=(lock_thread) (writeonly)

This method is for internal use only.
[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 207

def lock_thread=(lock_thread) # :nodoc:
  @lock =
  case lock_thread
  when Thread
    ActiveSupport::Concurrency::ThreadMonitor.new
  when Fiber
    ::Monitor.new
  else
    ActiveSupport::Concurrency::NullLock
  end
end

#logger (readonly)

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 58

attr_reader :visitor, :owner, :logger, :lock

#migration_strategy (readonly)

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 44

class_attribute :migration_strategy, instance_writer: false

#migration_strategy?Boolean (readonly)

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 44

class_attribute :migration_strategy, instance_writer: false

#owner (readonly) Also known as: #in_use?

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 58

attr_reader :visitor, :owner, :logger, :lock

#pinned (rw)

This method is for internal use only.
[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 60

attr_accessor :pinned # :nodoc:

#pool (rw)

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 57

attr_reader :pool

#pool=(value) (rw)

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 63

def pool=(value)
  return if value.eql?(@pool)
  @schema_cache = nil
  @pool = value
end

#prepared_statements (readonly)

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 262

alias :prepared_statements :prepared_statements?

#preventing_writes?Boolean (readonly)

Determines whether writes are currently being prevented.

Returns true if the connection is a replica or returns the value of current_preventing_writes.

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 252

def preventing_writes?
  return true if replica?
  return false if connection_descriptor.nil?

  connection_descriptor.current_preventing_writes
end

#reconnect_can_restore_state?Boolean (readonly, private)

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 1024

def reconnect_can_restore_state?
  transaction_manager.restorable? && !@raw_connection_dirty
end

#replica?Boolean (readonly)

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 224

def replica?
  @config[:replica] || false
end

#requires_reloading?Boolean (readonly)

Returns true if its required to reload the connection between requests for development mode.

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 815

def requires_reloading?
  false
end

#savepoint_errors_invalidate_transactions?Boolean (readonly)

Do TransactionRollbackErrors on savepoints affect the parent transaction?

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 438

def savepoint_errors_invalidate_transactions?
  false
end

#supports_advisory_locks?Boolean (readonly)

Does this adapter support application-enforced advisory locking?

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 447

def supports_advisory_locks?
  false
end

#supports_bulk_alter?Boolean (readonly)

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 427

def supports_bulk_alter?
  false
end

#supports_check_constraints?Boolean (readonly)

Does this adapter support creating check constraints?

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 519

def supports_check_constraints?
  false
end

#supports_comments?Boolean (readonly)

Does this adapter support metadata comments on database objects (tables, columns, indexes)?

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 554

def supports_comments?
  false
end

#supports_comments_in_create?Boolean (readonly)

Can comments for tables, columns, and indexes be specified in create/alter table statements?

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 559

def supports_comments_in_create?
  false
end

#supports_common_table_expressions?Boolean (readonly)

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 578

def supports_common_table_expressions?
  false
end

#supports_concurrent_connections?Boolean (readonly)

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 602

def supports_concurrent_connections?
  true
end

#supports_datetime_with_precision?Boolean (readonly)

Does this adapter support datetime with precision?

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 544

def supports_datetime_with_precision?
  false
end

#supports_ddl_transactions?Boolean (readonly)

Does this adapter support DDL rollbacks in transactions? That is, would CREATE TABLE or ALTER TABLE get rolled back by a transaction?

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 423

def supports_ddl_transactions?
  false
end

#supports_deferrable_constraints?Boolean (readonly)

Does this adapter support creating deferrable constraints?

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 514

def supports_deferrable_constraints?
  false
end

#supports_disabling_indexes?Boolean (readonly)

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 610

def supports_disabling_indexes?
  false
end

#supports_exclusion_constraints?Boolean (readonly)

Does this adapter support creating exclusion constraints?

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 524

def supports_exclusion_constraints?
  false
end

#supports_explain?Boolean (readonly)

Does this adapter support explain?

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 483

def supports_explain?
  false
end

#supports_expression_index?Boolean (readonly)

Does this adapter support expression indices?

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 478

def supports_expression_index?
  false
end

#supports_extensions?Boolean (readonly)

Does this adapter support database extensions?

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 493

def supports_extensions?
  false
end

#supports_foreign_keys?Boolean (readonly)

Does this adapter support creating foreign key constraints?

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 504

def supports_foreign_keys?
  false
end

#supports_foreign_tables?Boolean (readonly)

Does this adapter support foreign/external tables?

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 569

def supports_foreign_tables?
  false
end

#supports_index_include?Boolean (readonly)

Does this adapter support including non-key columns?

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 473

def supports_index_include?
  false
end

#supports_index_sort_order?Boolean (readonly)

Does this adapter support index sort order?

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 463

def supports_index_sort_order?
  false
end

#supports_indexes_in_create?Boolean (readonly)

Does this adapter support creating indexes in the same statement as creating the table?

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 499

def supports_indexes_in_create?
  false
end

#supports_insert_conflict_target?Boolean (readonly)

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 598

def supports_insert_conflict_target?
  false
end

#supports_insert_on_duplicate_skip?Boolean (readonly)

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 590

def supports_insert_on_duplicate_skip?
  false
end

#supports_insert_on_duplicate_update?Boolean (readonly)

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 594

def supports_insert_on_duplicate_update?
  false
end

#supports_insert_returning?Boolean (readonly)

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 586

def supports_insert_returning?
  false
end

#supports_json?Boolean (readonly)

Does this adapter support JSON data type?

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 549

def supports_json?
  false
end

#supports_lazy_transactions?Boolean (readonly)

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 582

def supports_lazy_transactions?
  false
end

#supports_materialized_views?Boolean (readonly)

Does this adapter support materialized views?

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 539

def supports_materialized_views?
  false
end

#supports_nulls_not_distinct?Boolean (readonly)

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 606

def supports_nulls_not_distinct?
  false
end

#supports_optimizer_hints?Boolean (readonly)

Does this adapter support optimizer hints?

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 574

def supports_optimizer_hints?
  false
end

#supports_partial_index?Boolean (readonly)

Does this adapter support partial indices?

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 468

def supports_partial_index?
  false
end

#supports_partitioned_indexes?Boolean (readonly)

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 458

def supports_partitioned_indexes?
  false
end

#supports_restart_db_transaction?Boolean (readonly)

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 442

def supports_restart_db_transaction?
  false
end

#supports_savepoints?Boolean (readonly)

Does this adapter support savepoints?

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 432

def supports_savepoints?
  false
end

#supports_transaction_isolation?Boolean (readonly)

Does this adapter support setting the isolation level for a transaction?

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 488

def supports_transaction_isolation?
  false
end

#supports_unique_constraints?Boolean (readonly)

Does this adapter support creating unique constraints?

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 529

def supports_unique_constraints?
  false
end

#supports_validate_constraints?Boolean (readonly)

Does this adapter support creating invalid constraints?

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 509

def supports_validate_constraints?
  false
end

#supports_views?Boolean (readonly)

Does this adapter support views?

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 534

def supports_views?
  false
end

#supports_virtual_columns?Boolean (readonly)

Does this adapter support virtual columns?

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 564

def supports_virtual_columns?
  false
end

#verified?Boolean (readonly)

This method is for internal use only.
[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 858

def verified? # :nodoc:
  @verified
end

#visitor (readonly)

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 58

attr_reader :visitor, :owner, :logger, :lock

Instance Method Details

#adapter_name

Returns the human-readable name of the adapter. Use mixed case - one can always use downcase if needed.

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 405

def adapter_name
  self.class::ADAPTER_NAME
end

#add_enum_value

This method is for internal use only.

This is meant to be implemented by the adapters that support custom enum types

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 644

def add_enum_value(...) # :nodoc:
end

#any_raw_connection (private)

Returns a raw connection for internal use with methods that are known to both be thread-safe and not rely upon actual server communication. This is useful for e.g. string escaping methods.

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 1167

def any_raw_connection
  @raw_connection || valid_raw_connection
end

#arel_visitor (private)

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 1300

def arel_visitor
  Arel::Visitors::ToSql.new(self)
end

#attempt_configure_connection (private)

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 1326

def attempt_configure_connection
  yield
rescue Exception # Need to handle things such as Timeout::ExitException
  disconnect!
  raise
end

#backoff(counter) (private)

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 1156

def backoff(counter)
  sleep 0.1 * counter
end

#build_insert_sql(insert)

This method is for internal use only.

Called by ::ActiveRecord::InsertAll, Passed an instance of ::ActiveRecord::InsertAll::Builder, This method implements standard bulk inserts for all databases, but should be overridden by adapters to implement common features with non-standard syntax like handling duplicates or returning values.

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 917

def build_insert_sql(insert) # :nodoc:
  if insert.skip_duplicates? || insert.update_duplicates?
    raise NotImplementedError, "#{self.class} should define `build_insert_sql` to implement adapter-specific logic for handling duplicates during INSERT"
  end

  "INSERT #{insert.into} #{insert.values_list}"
end

#build_result(columns:, rows:, column_types: nil) (private)

Builds the result object.

This is an internal hook to make possible connection adapters to build custom result objects with connection-specific data.

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 1311

def build_result(columns:, rows:, column_types: nil)
  ActiveRecord::Result.new(columns, rows, column_types)
end

#build_statement_pool (private)

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 1304

def build_statement_pool
end

#can_perform_case_insensitive_comparison_for?(column) ⇒ Boolean (private)

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 898

def can_perform_case_insensitive_comparison_for?(column)
  true
end

#case_insensitive_comparison(attribute, value)

This method is for internal use only.
[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 888

def case_insensitive_comparison(attribute, value) # :nodoc:
  column = column_for_attribute(attribute)

  if can_perform_case_insensitive_comparison_for?(column)
    attribute.lower.eq(attribute.relation.lower(value))
  else
    attribute.eq(value)
  end
end

#case_sensitive_comparison(attribute, value)

This method is for internal use only.
[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 884

def case_sensitive_comparison(attribute, value) # :nodoc:
  attribute.eq(value)
end

#check_all_foreign_keys_valid!

Override to check all foreign key constraints in a database. The adapter should raise a ::ActiveRecord::StatementInvalid if foreign key constraints are not met.

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 697

def check_all_foreign_keys_valid!
end

#check_version

This method is for internal use only.
[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 932

def check_version # :nodoc:
end

#clean!

This method is for internal use only.
[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 850

def clean! # :nodoc:
  _run_checkout_callbacks do
    @raw_connection_dirty = false
    @verified = nil
  end
  self
end

#clear_cache!(new_connection: false)

Clear any caching the database adapter may be doing.

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 802

def clear_cache!(new_connection: false)
  if @statements
    @lock.synchronize do
      if new_connection
        @statements.reset
      else
        @statements.clear
      end
    end
  end
end

#close

Check the connection back in to the connection pool

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 904

def close
  pool.checkin self
end

#collector (private)

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 1286

def collector
  if prepared_statements
    Arel::Collectors::Composite.new(
      Arel::Collectors::SQLString.new,
      Arel::Collectors::Bind.new,
    )
  else
    Arel::Collectors::SubstituteBinds.new(
      self,
      Arel::Collectors::SQLString.new,
    )
  end
end

#column_for(table_name, column_name) (private)

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 1275

def column_for(table_name, column_name)
  column_name = column_name.to_s
  columns(table_name).detect { |c| c.name == column_name } ||
    raise(ActiveRecordError, "No such column: #{table_name}.#{column_name}")
end

#column_for_attribute(attribute) (private)

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 1281

def column_for_attribute(attribute)
  table_name = attribute.relation.name
  schema_cache.columns_hash(table_name)[attribute.name.to_s]
end

#configure_connection (private)

Perform any necessary initialization upon the newly-established connection settings, run queries to configure any application-global “session” variables, etc.

Implementations may assume this method will only be called while holding @lock (or from #initialize).

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 1322

def configure_connection
  check_version
end

#connect!

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 845

def connect!
  verify!
  self
end

#connection_age

This method is for internal use only.

Seconds since this connection was established. nil if not connected; infinity if the connection has been explicitly retired.

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 384

def connection_age # :nodoc:
  if @raw_connection && @connected_since
    Process.clock_gettime(Process::CLOCK_MONOTONIC) - @connected_since
  end
end

#connection_descriptor

This method is for internal use only.
[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 311

def connection_descriptor # :nodoc:
  @pool.connection_descriptor
end

#connection_retries

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 228

def connection_retries
  (@config[:connection_retries] || 1).to_i
end

#create_enum

This method is for internal use only.

This is meant to be implemented by the adapters that support custom enum types

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 632

def create_enum(...) # :nodoc:
end

#create_virtual_table

This method is for internal use only.

This is meant to be implemented by the adapters that support virtual tables

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 652

def create_virtual_table(*) # :nodoc:
end

#database_version Also known as: #postgresql_version

This method is for internal use only.
[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 928

def database_version # :nodoc:
  pool.server_version(self)
end

#default_index_type?(index) ⇒ Boolean

This method is for internal use only.
[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 908

def default_index_type?(index) # :nodoc:
  index.using.nil?
end

#default_prepared_statements (private)

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 1333

def default_prepared_statements
  true
end

#default_timezone

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 244

def default_timezone
  @default_timezone || ActiveRecord.default_timezone
end

#default_uniqueness_comparison(attribute, value)

This method is for internal use only.
[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 880

def default_uniqueness_comparison(attribute, value) # :nodoc:
  attribute.eq(value)
end

#disable_extension(name)

This is meant to be implemented by the adapters that support extensions

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 624

def disable_extension(name, **)
end

#disable_referential_integrity

Override to turn off referential integrity while executing &block.

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 690

def disable_referential_integrity
  yield
end

#discard!

Immediately forget this connection ever existed. Unlike disconnect!, this will not communicate with the server.

After calling this method, the behavior of all other methods becomes undefined. This is called internally just before a forked process gets rid of a connection that belonged to its parent.

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 775

def discard!
  # This should be overridden by concrete adapters.
end

#disconnect!

Disconnects from the database if already connected. Otherwise, this method does nothing.

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 758

def disconnect!
  @lock.synchronize do
    clear_cache!(new_connection: true)
    reset_transaction
    @raw_connection_dirty = false
    @connected_since = nil
    @last_activity = nil
    @verified = false
  end
end

#drop_enum

This method is for internal use only.

This is meant to be implemented by the adapters that support custom enum types

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 636

def drop_enum(...) # :nodoc:
end

#drop_virtual_table

This method is for internal use only.

This is meant to be implemented by the adapters that support virtual tables

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 656

def drop_virtual_table(*) # :nodoc:
end

#enable_extension(name)

This is meant to be implemented by the adapters that support extensions

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 628

def enable_extension(name, **)
end

#expire(update_idle = true)

This method is for internal use only.

this method must only be called while holding connection pool’s mutex

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 336

def expire(update_idle = true) # :nodoc:
  if in_use?
    if @owner != ActiveSupport::IsolatedExecutionState.context
      raise ActiveRecordError, "Cannot expire connection, " \
        "it is owned by a different thread: #{@owner}. " \
        "Current thread: #{ActiveSupport::IsolatedExecutionState.context}."
    end

    _run_checkin_callbacks do
      @idle_since = Process.clock_gettime(Process::CLOCK_MONOTONIC) if update_idle
      @owner = nil
      enable_lazy_transactions!
      unset_query_cache!
    end
  else
    raise ActiveRecordError, "Cannot expire connection, it is not currently leased."
  end
end

#extended_type_map_key (private)

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 1184

def extended_type_map_key
  if @default_timezone
    { default_timezone: @default_timezone }
  end
end

#extensions

A list of extensions, to be filled in by adapters that support them.

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 678

def extensions
  []
end

#force_retirement

This method is for internal use only.

Mark the connection as needing to be retired, as if the age has exceeded the maximum allowed.

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 392

def force_retirement # :nodoc:
  @connected_since &&= -Float::INFINITY
end

#get_advisory_lock(lock_id)

This method is for internal use only.

This is meant to be implemented by the adapters that support advisory locks

Return true if we got the lock, otherwise false

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 667

def get_advisory_lock(lock_id) # :nodoc:
end

#get_database_version

This method is for internal use only.
[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 925

def get_database_version # :nodoc:
end

#index_algorithms

A list of index algorithms, to be filled by adapters that support them.

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 683

def index_algorithms
  {}
end

#inspect

This method is for internal use only.
[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 200

def inspect # :nodoc:
  name_field = " name=#{pool.db_config.name.inspect}" unless pool.db_config.name == "primary"
  shard_field = " shard=#{shard.inspect}" unless shard == :default

  "#<#{self.class.name}:#{'%#016x' % (object_id << 1)} env_name=#{pool.db_config.env_name.inspect}#{name_field} role=#{role.inspect}#{shard_field}>"
end

#instrumenter (private)

This method is for internal use only.
[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 1261

def instrumenter # :nodoc:
  ActiveSupport::IsolatedExecutionState[:active_record_instrumenter] ||= ActiveSupport::Notifications.instrumenter
end

#invalidate_transaction(exception) (private)

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 1142

def invalidate_transaction(exception)
  return unless exception.is_a?(TransactionRollbackError)
  return unless savepoint_errors_invalidate_transactions?

  current_transaction.invalidate!
end

#lease

this method must only be called while holding connection pool’s mutex

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 296

def lease
  if in_use?
    msg = +"Cannot lease connection, "
    if @owner == ActiveSupport::IsolatedExecutionState.context
      msg << "it is already leased by the current thread."
    else
      msg << "it is already in use by a different thread: #{@owner}. " \
             "Current thread: #{ActiveSupport::IsolatedExecutionState.context}."
    end
    raise ActiveRecordError, msg
  end

  @owner = ActiveSupport::IsolatedExecutionState.context
end

#log(intent_or_sql, name = "SQL", binds = [], type_casted_binds = [], async: false, allow_retry: false, &block) (private)

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 1212

def log(intent_or_sql, name = "SQL", binds = [], type_casted_binds = [], async: false, allow_retry: false, &block)
  if intent_or_sql.is_a?(QueryIntent)
    intent = intent_or_sql

    instrumenter.instrument(
      "sql.active_record",
      sql:               intent.processed_sql,
      name:              intent.name,
      binds:             intent.binds,
      type_casted_binds: intent.type_casted_binds,
      async:             intent.ran_async,
      allow_retry:       intent.allow_retry,
      connection:        self,
      transaction:       current_transaction.user_transaction.presence,
      affected_rows:     0,
      row_count:         0,
      &block
    )
  else
    ActiveRecord.deprecator.warn(<<-MSG.squish)
      Passing SQL strings to `log` is deprecated and will stop working in Rails 8.2.
      Please pass a `QueryIntent` object instead.
    MSG

    sql = intent_or_sql

    instrumenter.instrument(
      "sql.active_record",
      sql:               sql,
      name:              name,
      binds:             binds,
      type_casted_binds: type_casted_binds,
      async:             async,
      allow_retry:       allow_retry,
      connection:        self,
      transaction:       current_transaction.user_transaction.presence,
      affected_rows:     0,
      row_count:         0,
      &block
    )
  end
rescue ActiveRecord::StatementInvalid => ex
  if intent
    raise ex.set_query(intent.processed_sql, intent.binds)
  else
    raise ex.set_query(sql, binds)
  end
end

#max_jitter

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 220

def max_jitter
  (@config[:pool_jitter] || 0.2).to_f.clamp(MAX_JITTER)
end

#native_database_types

This method is for internal use only.
[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 291

def native_database_types # :nodoc:
  self.class.native_database_types
end

#pool_jitter(duration)

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 331

def pool_jitter(duration)
  duration * (1.0 - @pool_jitter)
end

#prefetch_primary_key?(table_name = nil) ⇒ Boolean

Should primary key values be selected from their corresponding sequence before the insert statement? If true, next_sequence_value is called before each insert to set the record’s primary key.

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 454

def prefetch_primary_key?(table_name = nil)
  false
end

#prepared_statements?Boolean (readonly) Also known as: #prepared_statements

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 259

def prepared_statements?
  @prepared_statements && !prepared_statements_disabled_cache.include?(object_id)
end

#prepared_statements_disabled_cache

This method is for internal use only.
[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 264

def prepared_statements_disabled_cache # :nodoc:
  ActiveSupport::IsolatedExecutionState[:active_record_prepared_statements_disabled_cache] ||= Set.new
end

#raw_connection

Provides access to the underlying database driver for this adapter. For example, this method returns a Mysql2::Client object in case of Mysql2Adapter, and a PG::Connection object in case of PostgreSQLAdapter.

This is useful for when you need to call a proprietary method such as PostgreSQL’s lo_* methods.

Active Record cannot track if the database is getting modified using this client. If that is the case, generally you’ll want to invalidate the query cache using ActiveRecord::Base.clear_query_cache.

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 872

def raw_connection
  with_raw_connection do |conn|
    disable_lazy_transactions!
    @raw_connection_dirty = true
    conn
  end
end

#reconnect (private)

Raises:

  • (NotImplementedError)
[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 1160

def reconnect
  raise NotImplementedError.new("#{self.class} should define `reconnect` to implement adapter-specific logic for reconnecting to the database")
end

#reconnect!(restore_transactions: false)

Disconnects from the database if already connected, and establishes a new connection with the database. Implementors should define private #reconnect instead.

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 718

def reconnect!(restore_transactions: false)
  retries_available = connection_retries
  deadline = retry_deadline && Process.clock_gettime(Process::CLOCK_MONOTONIC) + retry_deadline

  @lock.synchronize do
    attempt_configure_connection do
      @allow_preconnect = false

      reconnect

      enable_lazy_transactions!
      @raw_connection_dirty = false
      @last_activity = @connected_since = Process.clock_gettime(Process::CLOCK_MONOTONIC)
      @verified = true
      @allow_preconnect = true

      reset_transaction(restore: restore_transactions) do
        clear_cache!(new_connection: true)
        configure_connection
      end
    rescue => original_exception
      translated_exception = translate_exception_class(original_exception, nil, nil)
      retry_deadline_exceeded = deadline && deadline < Process.clock_gettime(Process::CLOCK_MONOTONIC)

      if !retry_deadline_exceeded && retries_available > 0
        retries_available -= 1

        if retryable_connection_error?(translated_exception)
          backoff(connection_retries - retries_available)
          retry
        end
      end

      raise translated_exception
    end
  end
end

#release_advisory_lock(lock_id)

This method is for internal use only.

This is meant to be implemented by the adapters that support advisory locks.

Return true if we released the lock, otherwise false

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 674

def release_advisory_lock(lock_id) # :nodoc:
end

#rename_enum

This method is for internal use only.

This is meant to be implemented by the adapters that support custom enum types

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 640

def rename_enum(...) # :nodoc:
end

#rename_enum_value

This method is for internal use only.

This is meant to be implemented by the adapters that support custom enum types

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 648

def rename_enum_value(...) # :nodoc:
end

#reset!

Reset the state of this connection, directing the DBMS to clear transactions and other connection-related server-side state. Usually a database-dependent operation.

If a database driver or protocol does not support such a feature, implementors may alias this to #reconnect!. Otherwise, implementors should call super immediately after resetting the connection (and while still holding @lock).

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 787

def reset!
  attempt_configure_connection do
    clear_cache!(new_connection: true)
    reset_transaction
    configure_connection
  end
end

#retry_deadline

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 236

def retry_deadline
  if @config[:retry_deadline]
    @config[:retry_deadline].to_f
  else
    nil
  end
end

#retryable_connection_error?(exception) ⇒ Boolean (private)

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 1137

def retryable_connection_error?(exception)
  (exception.is_a?(ConnectionNotEstablished) && !exception.is_a?(ConnectionNotDefined)) ||
    exception.is_a?(ConnectionFailed)
end

#retryable_query_error?(exception) ⇒ Boolean (private)

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 1149

def retryable_query_error?(exception)
  # We definitely can't retry if we were inside an invalidated transaction.
  return false if current_transaction.invalidated?

  exception.is_a?(Deadlocked) || exception.is_a?(LockWaitTimeout)
end

#return_value_after_insert?(column) ⇒ Boolean

This method is for internal use only.
[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 614

def return_value_after_insert?(column) # :nodoc:
  column.auto_populated?
end

#role

The role (e.g. :writing) for the current connection. In a non-multi role application, :writing is returned.

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 317

def role
  @pool.role
end

#schema_cache

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 327

def schema_cache
  @pool.schema_cache || (@schema_cache ||= BoundSchemaReflection.for_lone_connection(@pool.schema_reflection, self))
end

#schema_version

Returns the version identifier of the schema currently available in the database. This is generally equal to the number of the highest- numbered migration that has been executed, or 0 if no schema information is present / the database is empty.

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 939

def schema_version
  pool.migration_context.current_version
end

#seconds_idle

This method is for internal use only.

Seconds since this connection was returned to the pool

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 369

def seconds_idle # :nodoc:
  return 0 if in_use?
  Process.clock_gettime(Process::CLOCK_MONOTONIC) - @idle_since
end

#seconds_since_last_activity

This method is for internal use only.

Seconds since this connection last communicated with the server

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 375

def seconds_since_last_activity # :nodoc:
  if @raw_connection && @last_activity
    Process.clock_gettime(Process::CLOCK_MONOTONIC) - @last_activity
  end
end

#shard

The shard (e.g. :default) for the current connection. In a non-sharded application, :default is returned.

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 323

def shard
  @pool.shard
end

#steal!

This method is for internal use only.

this method must only be called while holding connection pool’s mutex (and a desire for segfaults)

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 356

def steal! # :nodoc:
  if in_use?
    if @owner != ActiveSupport::IsolatedExecutionState.context
      pool.send :remove_connection_from_thread_cache, self, @owner

      @owner = ActiveSupport::IsolatedExecutionState.context
    end
  else
    raise ActiveRecordError, "Cannot steal connection, it is not currently leased."
  end
end

#throw_away!

Removes the connection from the pool and disconnect it.

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 796

def throw_away!
  pool.remove self
  disconnect!
end

#translate_exception(exception, message:, sql:, binds:) (private)

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 1265

def translate_exception(exception, message:, sql:, binds:)
  # override in derived class
  case exception
  when RuntimeError, ActiveRecord::ActiveRecordError
    exception
  else
    ActiveRecord::StatementInvalid.new(message, sql: sql, binds: binds, connection_pool: @pool)
  end
end

#translate_exception_class(native_error, sql, binds) (private)

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 1200

def translate_exception_class(native_error, sql, binds)
  return native_error if native_error.is_a?(ActiveRecordError)

  message = "#{native_error.class.name}: #{native_error.message}"

  active_record_error = translate_exception(
    native_error, message: message, sql: sql, binds: binds
  )
  active_record_error.set_backtrace(native_error.backtrace)
  active_record_error
end

#type_map (private)

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 1190

def type_map
  if key = extended_type_map_key
    self.class::EXTENDED_TYPE_MAPS.compute_if_absent(key) do
      self.class.extended_type_map(**key)
    end
  else
    self.class::TYPE_MAP
  end
end

#unprepared_statement

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 396

def unprepared_statement
  cache = prepared_statements_disabled_cache.add?(object_id) if @prepared_statements
  yield
ensure
  cache&.delete(object_id)
end

#valid_raw_connection (private)

Similar to any_raw_connection, but ensures it is validated and connected. Any method called on this result still needs to be independently thread-safe, so it probably shouldn’t talk to the server… but some drivers fail if they know the connection has gone away.

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 1176

def valid_raw_connection
  (@verified && @raw_connection) ||
    # `allow_retry: false`, to force verification: the block won't
    # raise, so a retry wouldn't help us get the valid connection we
    # need.
    with_raw_connection(allow_retry: false, materialize_transactions: false) { |conn| conn }
end

#valid_type?(type) ⇒ Boolean

This method is for internal use only.
[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 287

def valid_type?(type) # :nodoc:
  self.class.valid_type?(type)
end

#verified! (private)

Mark the connection as verified. Call this inside a #with_raw_connection block only when the block is guaranteed to exercise the raw connection.

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 1132

def verified!
  @last_activity = Process.clock_gettime(Process::CLOCK_MONOTONIC)
  @verified = true
end

#verify!

Checks whether the connection to the database is still active (i.e. not stale). This is done under the hood by calling #active?. If the connection is no longer active, then this method will reconnect to the database.

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 822

def verify!
  unless active?
    @lock.synchronize do
      if @unconfigured_connection
        attempt_configure_connection do
          @raw_connection = @unconfigured_connection
          @unconfigured_connection = nil
          configure_connection
          @last_activity = Process.clock_gettime(Process::CLOCK_MONOTONIC)
          @verified = true
          @allow_preconnect = true
        end
        return
      end

      reconnect!(restore_transactions: true)
    end
  end

  @last_activity = Process.clock_gettime(Process::CLOCK_MONOTONIC)
  @verified = true
end

#verify_timeout

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 232

def verify_timeout
  (@config[:verify_timeout] || 2).to_i
end

#warning_ignored?(warning) ⇒ Boolean (private)

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 1337

def warning_ignored?(warning)
  ActiveRecord.db_warnings_ignore.any? do |warning_matcher|
    warning.message.match?(warning_matcher) || warning.code.to_s.match?(warning_matcher)
  end
end

#with_raw_connection(allow_retry: false, materialize_transactions: true) (private)

Lock the monitor, ensure we’re properly connected and transactions are materialized, and then yield the underlying raw connection object.

If allow_retry is true, a connection-related exception will cause an automatic reconnect and re-run of the block, up to the connection’s configured #connection_retries setting and the configured #retry_deadline limit. (Note that when allow_retry is true, it’s possible to return without having marked the connection as verified. If the block is guaranteed to exercise the connection, consider calling #verified! to avoid needless verification queries in subsequent calls.)

If materialize_transactions is false, the block will be run without ensuring virtual transactions have been materialized in the DB server’s state. The active transaction will also remain clean (if it is not already dirty), meaning it’s able to be restored by reconnecting and opening an equivalent-depth set of new transactions. This should only be used by transaction control methods, and internal transaction-agnostic queries.

It’s not the primary use case, so not something to optimize for, but note that this method does need to be re-entrant: materialize_transactions will re-enter if it has work to do, and the yield block can also do so under some circumstances.

In the latter case, we really ought to guarantee the inner call will not reconnect (which would interfere with the still-yielded connection in the outer block), but we currently provide no special enforcement there.

[ GitHub ]

  
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 1061

def with_raw_connection(allow_retry: false, materialize_transactions: true)
  @lock.synchronize do
    connect! if @raw_connection.nil? && reconnect_can_restore_state?

    self.materialize_transactions if materialize_transactions

    retries_available = allow_retry ? connection_retries : 0
    deadline = retry_deadline && Process.clock_gettime(Process::CLOCK_MONOTONIC) + retry_deadline
    reconnectable = reconnect_can_restore_state?

    if @verified
      # Cool, we're confident the connection's ready to use. (Note this might have
      # become true during the above #materialize_transactions.)
    elsif (last_activity = seconds_since_last_activity) && last_activity < verify_timeout
      # We haven't actually verified the connection since we acquired it, but it
      # has been used very recently. We're going to assume it's still okay.
    elsif reconnectable
      if allow_retry
        # Not sure about the connection yet, but if anything goes wrong we can
        # just reconnect and re-run our query
      else
        # We can reconnect if needed, but we don't trust the upcoming query to be
        # safely re-runnable: let's verify the connection to be sure
        verify!
      end
    else
      # We don't know whether the connection is okay, but it also doesn't matter:
      # we wouldn't be able to reconnect anyway. We're just going to run our query
      # and hope for the best.
    end

    begin
      yield @raw_connection
    rescue => original_exception
      translated_exception = translate_exception_class(original_exception, nil, nil)
      invalidate_transaction(translated_exception)
      retry_deadline_exceeded = deadline && deadline < Process.clock_gettime(Process::CLOCK_MONOTONIC)

      if !retry_deadline_exceeded && retries_available > 0
        retries_available -= 1

        if retryable_query_error?(translated_exception)
          backoff(connection_retries - retries_available)
          retry
        elsif reconnectable && retryable_connection_error?(translated_exception)
          reconnect!(restore_transactions: true)
          # Only allowed to reconnect once, because reconnect! has its own retry
          # loop
          reconnectable = false
          retry
        end
      end

      unless retryable_query_error?(translated_exception)
        # Barring a known-retryable error inside the query (regardless of
        # whether we were in a _position_ to retry it), we should infer that
        # there's likely a real problem with the connection.
        @last_activity = nil
        @verified = false
      end

      raise translated_exception
    ensure
      dirty_current_transaction if materialize_transactions
    end
  end
end