Class: ActiveRecord::ConnectionAdapters::AbstractAdapter
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Extension / Inclusion / Inheritance Descendants | |
Subclasses:
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Super Chains via Extension / Inclusion / Inheritance | |
Class Chain:
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Instance Chain:
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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.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
-
ADAPTER_NAME =
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 32"Abstract"
-
COMMENT_REGEX =
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 42%r{(?:--.*\n)|/\*(?:[^*]|\*[^/])*\*/}
-
EXTENDED_TYPE_MAPS =
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 958Concurrent::Map.new
-
FIBER_LOCK =
private
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 180ActiveSupport::Concurrency::LoadInterlockAwareMonitor.new
-
SIMPLE_INT =
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 41/\A\d+\z/
-
THREAD_LOCK =
private
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 177ActiveSupport::Concurrency::ThreadLoadInterlockAwareMonitor.new
-
TYPE_MAP =
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 957Type::TypeMap.new.tap { |m| initialize_type_map(m) }
::ActiveSupport::Callbacks
- Included
DatabaseStatements
- Included
DEFAULT_INSERT_VALUE
Quoting
- Included
COLUMN_NAME, COLUMN_NAME_WITH_ORDER
::ActiveSupport::Callbacks
- Attributes & Methods
- .__callbacks rw
- #__callbacks readonly
- .__callbacks? ⇒ Boolean rw
- #__callbacks? ⇒ Boolean readonly
Class Method Summary
-
.database_exists?(config) ⇒ Boolean
Does the database for this adapter exist?
-
.dbconsole(config, options = {})
Opens a database console session.
- .find_cmd_and_exec(commands, *args)
- .type_cast_config_to_boolean(config)
- .type_cast_config_to_integer(config)
- .validate_default_timezone(config)
::ActiveSupport::DescendantsTracker
- self
descendants | See additional method definition at line 104. |
subclasses | See additional method definition at line 100. |
Instance Attribute Summary
-
#active? ⇒ Boolean
readonly
Checks whether the connection to the database is still active.
-
#all_foreign_keys_valid? ⇒ Boolean
readonly
Override to check all foreign key constraints in a database.
- #database_exists? ⇒ Boolean readonly
-
#in_use?
readonly
Alias for #owner.
- #lock readonly
- #logger readonly
- #owner (also: #in_use?) readonly
- #pool rw
- #pool=(value) rw
-
#prepared_statements
readonly
Alias for #prepared_statements?.
-
#preventing_writes? ⇒ Boolean
readonly
Determines whether writes are currently being prevented.
- #replica? ⇒ Boolean readonly
-
#requires_reloading? ⇒ Boolean
readonly
Returns true if its required to reload the connection between requests for development mode.
-
#savepoint_errors_invalidate_transactions? ⇒ Boolean
readonly
Do TransactionRollbackErrors on savepoints affect the parent transaction?
-
#supports_advisory_locks? ⇒ Boolean
readonly
Does this adapter support application-enforced advisory locking?
- #supports_bulk_alter? ⇒ Boolean readonly
-
#supports_check_constraints? ⇒ Boolean
readonly
Does this adapter support creating check constraints?
-
#supports_comments? ⇒ Boolean
readonly
Does this adapter support metadata comments on database objects (tables, columns, indexes)?
-
#supports_comments_in_create? ⇒ Boolean
readonly
Can comments for tables, columns, and indexes be specified in create/alter table statements?
- #supports_common_table_expressions? ⇒ Boolean readonly
- #supports_concurrent_connections? ⇒ Boolean readonly
-
#supports_datetime_with_precision? ⇒ Boolean
readonly
Does this adapter support datetime with precision?
-
#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?
-
#supports_deferrable_constraints? ⇒ Boolean
readonly
Does this adapter support creating deferrable constraints?
-
#supports_exclusion_constraints? ⇒ Boolean
readonly
Does this adapter support creating exclusion constraints?
-
#supports_explain? ⇒ Boolean
readonly
Does this adapter support explain?
-
#supports_expression_index? ⇒ Boolean
readonly
Does this adapter support expression indices?
-
#supports_extensions? ⇒ Boolean
readonly
Does this adapter support database extensions?
-
#supports_foreign_keys? ⇒ Boolean
readonly
Does this adapter support creating foreign key constraints?
-
#supports_foreign_tables? ⇒ Boolean
readonly
Does this adapter support foreign/external tables?
-
#supports_index_include? ⇒ Boolean
readonly
Does this adapter support including non-key columns?
-
#supports_index_sort_order? ⇒ Boolean
readonly
Does this adapter support index sort order?
-
#supports_indexes_in_create? ⇒ Boolean
readonly
Does this adapter support creating indexes in the same statement as creating the table?
- #supports_insert_conflict_target? ⇒ Boolean readonly
- #supports_insert_on_duplicate_skip? ⇒ Boolean readonly
- #supports_insert_on_duplicate_update? ⇒ Boolean readonly
- #supports_insert_returning? ⇒ Boolean readonly
-
#supports_json? ⇒ Boolean
readonly
Does this adapter support JSON data type?
- #supports_lazy_transactions? ⇒ Boolean readonly
-
#supports_materialized_views? ⇒ Boolean
readonly
Does this adapter support materialized views?
- #supports_nulls_not_distinct? ⇒ Boolean readonly
-
#supports_optimizer_hints? ⇒ Boolean
readonly
Does this adapter support optimizer hints?
-
#supports_partial_index? ⇒ Boolean
readonly
Does this adapter support partial indices?
- #supports_partitioned_indexes? ⇒ Boolean readonly
- #supports_restart_db_transaction? ⇒ Boolean readonly
-
#supports_savepoints? ⇒ Boolean
readonly
Does this adapter support savepoints?
-
#supports_transaction_isolation? ⇒ Boolean
readonly
Does this adapter support setting the isolation level for a transaction?
-
#supports_unique_constraints? ⇒ Boolean
readonly
Does this adapter support creating unique constraints?
-
#supports_validate_constraints? ⇒ Boolean
readonly
Does this adapter support creating invalid constraints?
-
#supports_views? ⇒ Boolean
readonly
Does this adapter support views?
-
#supports_virtual_columns? ⇒ Boolean
readonly
Does this adapter support virtual columns?
- #use_metadata_table? ⇒ Boolean readonly
- #visitor readonly
DatabaseStatements
- Included
SchemaStatements
- Included
Instance Method Summary
-
#adapter_name
Returns the human-readable name of the adapter.
-
#check_all_foreign_keys_valid!
Override to check all foreign key constraints in a database.
-
#clear_cache!(new_connection: false)
Clear any caching the database adapter may be doing.
-
#close
Check the connection back in to the connection pool.
- #connect!
- #connection_retries
- #default_timezone
-
#disable_extension(name)
This is meant to be implemented by the adapters that support extensions.
-
#disable_referential_integrity
Override to turn off referential integrity while executing
&block
. -
#discard!
Immediately forget this connection ever existed.
-
#disconnect!
Disconnects from the database if already connected.
-
#enable_extension(name)
This is meant to be implemented by the adapters that support extensions.
-
#expire
this method must only be called while holding connection pool’s mutex.
-
#extensions
A list of extensions, to be filled in by adapters that support them.
-
#index_algorithms
A list of index algorithms, to be filled by adapters that support them.
-
#lease
this method must only be called while holding connection pool’s mutex.
-
#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.
- #prepared_statements? ⇒ Boolean (also: #prepared_statements) readonly
-
#raw_connection
Provides access to the underlying database driver for this adapter.
-
#reconnect!(restore_transactions: false)
Disconnects from the database if already connected, and establishes a new connection with the database.
-
#reset!
Reset the state of this connection, directing the DBMS to clear transactions and other connection-related server-side state.
- #retry_deadline
-
#role
The role (e.g.
:writing
) for the current connection. - #schema_cache
-
#schema_version
Returns the version identifier of the schema currently available in the database.
-
#shard
The shard (e.g.
:default
) for the current connection. -
#throw_away!
Removes the connection from the pool and disconnect it.
- #unprepared_statement
-
#verify!
Checks whether the connection to the database is still active (i.e. not stale).
- #log(sql, name = "SQL", binds = [], type_casted_binds = [], statement_name = nil, async: false, &block) private
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. |
Quoting
- Included
#quote | Quotes the column value to help prevent SQL injection attacks. |
#quote_bound_value | Quote a value to be used as a bound parameter of unknown type. |
#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 |
#unquoted_false, #unquoted_true |
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 | Alias for DatabaseStatements#insert. |
#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 |
#exec_insert | Executes insert |
#exec_query | Executes |
#exec_update | Executes update |
#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 |
#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_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, | |
#sanitize_limit | Sanitizes the given LIMIT parameter in order to prevent SQL injection. |
#select_all | Returns an |
#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. |
SchemaStatements
- Included
#add_belongs_to | Alias for SchemaStatements#add_reference. |
#add_check_constraint | Adds a new check constraint to the table. |
#add_column | Add a new |
#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 ( |
#assume_migrated_upto_version, | |
#build_create_table_definition | Returns a |
#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 |
#change_column_default | Sets a new default value for a column: |
#change_column_null | Sets or removes a |
#change_table | A block for changing columns in |
#change_table_comment | Changes the comment for a table or removes it if |
#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 |
#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 |
#data_source_exists? | Checks to see if the data source |
#data_sources | Returns the relation names usable to back Active Record models. |
#drop_join_table | Drops the join table specified by the given arguments. |
#drop_table | Drops a table from the database. |
#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 | Alias for SchemaStatements#remove_reference. |
#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 ( |
#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_options, | |
#tables | Returns an array of table names defined in the database. |
#view_exists? | Checks to see if the view |
#views | Returns an array of view names defined in the database. |
::ActiveSupport::Callbacks
- Included
#run_callbacks | Runs the callbacks for the given event. |
Class Attribute Details
.__callbacks (rw)
[ GitHub ]# File 'activesupport/lib/active_support/callbacks.rb', line 70
class_attribute :__callbacks, instance_writer: false, default: {}
.__callbacks? ⇒ Boolean
(rw)
[ GitHub ]
# File 'activesupport/lib/active_support/callbacks.rb', line 70
class_attribute :__callbacks, instance_writer: false, default: {}
Class Method Details
.database_exists?(config) ⇒ Boolean
Does the database for this adapter exist?
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 382
def self.database_exists?(config) new(config).database_exists? end
.dbconsole(config, options = {})
Opens a database console session.
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 124
def self.dbconsole(config, = {}) raise NotImplementedError end
.find_cmd_and_exec(commands, *args)
[ GitHub ]# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 95
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
.type_cast_config_to_boolean(config)
[ GitHub ]# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 68
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 58
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
.validate_default_timezone(config)
[ GitHub ]# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 76
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, default: {}
#__callbacks? ⇒ Boolean
(readonly)
[ GitHub ]
# File 'activesupport/lib/active_support/callbacks.rb', line 70
class_attribute :__callbacks, instance_writer: 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.
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 674
def active? end
#all_foreign_keys_valid? ⇒ Boolean
(readonly)
Override to check all foreign key constraints in a database.
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 655
def all_foreign_keys_valid? check_all_foreign_keys_valid! true rescue ActiveRecord::StatementInvalid false end
#database_exists? ⇒ Boolean
(readonly)
[ GitHub ]
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 386
def database_exists? connect! true rescue ActiveRecord::NoDatabaseError false end
#in_use? (readonly)
Alias for #owner.
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 46
alias :in_use? :owner
#lock (readonly)
[ GitHub ]#logger (readonly)
[ GitHub ]#owner (readonly) Also known as: #in_use?
[ GitHub ]#pool (rw)
[ GitHub ]# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 44
attr_reader :pool
#pool=(value) (rw)
[ GitHub ]# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 48
def pool=(value) return if value.eql?(@pool) @schema_cache = nil @pool = value @pool.schema_reflection.load!(self) if ActiveRecord.lazily_load_schema_cache end
#prepared_statements (readonly)
Alias for #prepared_statements?.
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 268
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
.
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 242
def preventing_writes? return true if replica? return false if connection_class.nil? connection_class.current_preventing_writes end
#replica? ⇒ Boolean
(readonly)
[ GitHub ]
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 214
def replica? @config[:replica] || false end
#requires_reloading? ⇒ Boolean
(readonly)
Returns true if its required to reload the connection between requests for development mode.
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 768
def requires_reloading? false end
#savepoint_errors_invalidate_transactions? ⇒ Boolean
(readonly)
Do TransactionRollbackErrors on savepoints affect the parent transaction?
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 410
def savepoint_errors_invalidate_transactions? false end
#supports_advisory_locks? ⇒ Boolean
(readonly)
Does this adapter support application-enforced advisory locking?
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 419
def supports_advisory_locks? false end
#supports_bulk_alter? ⇒ Boolean
(readonly)
[ GitHub ]
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 399
def supports_bulk_alter? false end
#supports_check_constraints? ⇒ Boolean
(readonly)
Does this adapter support creating check constraints?
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 491
def supports_check_constraints? false end
#supports_comments? ⇒ Boolean
(readonly)
Does this adapter support metadata comments on database objects (tables, columns, indexes)?
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 526
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?
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 531
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 550
def supports_common_table_expressions? false end
#supports_concurrent_connections? ⇒ Boolean
(readonly)
[ GitHub ]
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 574
def supports_concurrent_connections? true end
#supports_datetime_with_precision? ⇒ Boolean
(readonly)
Does this adapter support datetime with precision?
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 516
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?
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 395
def supports_ddl_transactions? false end
#supports_deferrable_constraints? ⇒ Boolean
(readonly)
Does this adapter support creating deferrable constraints?
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 486
def supports_deferrable_constraints? false end
#supports_exclusion_constraints? ⇒ Boolean
(readonly)
Does this adapter support creating exclusion constraints?
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 496
def supports_exclusion_constraints? false end
#supports_explain? ⇒ Boolean
(readonly)
Does this adapter support explain?
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 455
def supports_explain? false end
#supports_expression_index? ⇒ Boolean
(readonly)
Does this adapter support expression indices?
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 450
def supports_expression_index? false end
#supports_extensions? ⇒ Boolean
(readonly)
Does this adapter support database extensions?
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 465
def supports_extensions? false end
#supports_foreign_keys? ⇒ Boolean
(readonly)
Does this adapter support creating foreign key constraints?
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 476
def supports_foreign_keys? false end
#supports_foreign_tables? ⇒ Boolean
(readonly)
Does this adapter support foreign/external tables?
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 541
def supports_foreign_tables? false end
#supports_index_include? ⇒ Boolean
(readonly)
Does this adapter support including non-key columns?
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 445
def supports_index_include? false end
#supports_index_sort_order? ⇒ Boolean
(readonly)
Does this adapter support index sort order?
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 435
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?
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 471
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 570
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 562
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 566
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 558
def supports_insert_returning? false end
#supports_json? ⇒ Boolean
(readonly)
Does this adapter support JSON data type?
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 521
def supports_json? false end
#supports_lazy_transactions? ⇒ Boolean
(readonly)
[ GitHub ]
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 554
def supports_lazy_transactions? false end
#supports_materialized_views? ⇒ Boolean
(readonly)
Does this adapter support materialized views?
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 511
def supports_materialized_views? false end
#supports_nulls_not_distinct? ⇒ Boolean
(readonly)
[ GitHub ]
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 578
def supports_nulls_not_distinct? false end
#supports_optimizer_hints? ⇒ Boolean
(readonly)
Does this adapter support optimizer hints?
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 546
def supports_optimizer_hints? false end
#supports_partial_index? ⇒ Boolean
(readonly)
Does this adapter support partial indices?
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 440
def supports_partial_index? false end
#supports_partitioned_indexes? ⇒ Boolean
(readonly)
[ GitHub ]
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 430
def supports_partitioned_indexes? false end
#supports_restart_db_transaction? ⇒ Boolean
(readonly)
[ GitHub ]
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 414
def supports_restart_db_transaction? false end
#supports_savepoints? ⇒ Boolean
(readonly)
Does this adapter support savepoints?
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 404
def supports_savepoints? false end
#supports_transaction_isolation? ⇒ Boolean
(readonly)
Does this adapter support setting the isolation level for a transaction?
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 460
def supports_transaction_isolation? false end
#supports_unique_constraints? ⇒ Boolean
(readonly)
Does this adapter support creating unique constraints?
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 501
def supports_unique_constraints? false end
#supports_validate_constraints? ⇒ Boolean
(readonly)
Does this adapter support creating invalid constraints?
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 481
def supports_validate_constraints? false end
#supports_views? ⇒ Boolean
(readonly)
Does this adapter support views?
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 506
def supports_views? false end
#supports_virtual_columns? ⇒ Boolean
(readonly)
Does this adapter support virtual columns?
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 536
def supports_virtual_columns? false end
#use_metadata_table? ⇒ Boolean
(readonly)
[ GitHub ]
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 218
def @config.fetch(:, true) end
#visitor (readonly)
[ GitHub ]Instance Method Details
#adapter_name
Returns the human-readable name of the adapter. Use mixed case - one can always use downcase if needed.
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 377
def adapter_name self.class::ADAPTER_NAME 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.
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 666
def check_all_foreign_keys_valid! end
#clear_cache!(new_connection: false)
Clear any caching the database adapter may be doing.
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 755
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
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 845
def close pool.checkin self end
#connect!
[ GitHub ]# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 793
def connect! verify! self end
#connection_retries
[ GitHub ]# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 222
def connection_retries (@config[:connection_retries] || 1).to_i end
#default_timezone
[ GitHub ]# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 234
def default_timezone @default_timezone || ActiveRecord.default_timezone end
#disable_extension(name)
This is meant to be implemented by the adapters that support extensions
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 592
def disable_extension(name, **) end
#disable_referential_integrity
Override to turn off referential integrity while executing &block
.
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 650
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.
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 730
def discard! # This should be overridden by concrete adapters. end
#disconnect!
Disconnects from the database if already connected. Otherwise, this method does nothing.
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 716
def disconnect! @lock.synchronize do clear_cache!(new_connection: true) reset_transaction @raw_connection_dirty = false end end
#enable_extension(name)
This is meant to be implemented by the adapters that support extensions
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 596
def enable_extension(name, **) end
#expire
this method must only be called while holding connection pool’s mutex
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 334
def expire 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 @idle_since = Process.clock_gettime(Process::CLOCK_MONOTONIC) @owner = nil else raise ActiveRecordError, "Cannot expire connection, it is not currently leased." end end
#extensions
A list of extensions, to be filled in by adapters that support them.
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 638
def extensions [] end
#index_algorithms
A list of index algorithms, to be filled by adapters that support them.
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 643
def index_algorithms {} end
#lease
this method must only be called while holding connection pool’s mutex
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 298
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(sql, name = "SQL", binds = [], type_casted_binds = [], statement_name = nil, async: false, &block) (private)
[ GitHub ]# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 1141
def log(sql, name = "SQL", binds = [], type_casted_binds = [], statement_name = nil, async: false, &block) # :doc: @instrumenter.instrument( "sql.active_record", sql: sql, name: name, binds: binds, type_casted_binds: type_casted_binds, statement_name: statement_name, async: async, connection: self, &block ) rescue ActiveRecord::StatementInvalid => ex raise ex.set_query(sql, binds) 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.
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 426
def prefetch_primary_key?(table_name = nil) false end
#prepared_statements? ⇒ Boolean
(readonly)
Also known as: #prepared_statements
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 265
def prepared_statements? @prepared_statements && !prepared_statements_disabled_cache.include?(object_id) 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
.
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 813
def raw_connection with_raw_connection do |conn| disable_lazy_transactions! @raw_connection_dirty = true conn end 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.
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 680
def reconnect!(restore_transactions: false) retries_available = connection_retries deadline = retry_deadline && Process.clock_gettime(Process::CLOCK_MONOTONIC) + retry_deadline @lock.synchronize do reconnect enable_lazy_transactions! @raw_connection_dirty = false @verified = 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 @verified = false raise translated_exception end 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).
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 742
def reset! clear_cache!(new_connection: true) reset_transaction configure_connection end
#retry_deadline
[ GitHub ]# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 226
def retry_deadline if @config[:retry_deadline] @config[:retry_deadline].to_f else nil end end
#role
The role (e.g. :writing
) for the current connection. In a non-multi role application, :writing
is returned.
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 319
def role @pool.role end
#schema_cache
[ GitHub ]# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 329
def schema_cache @schema_cache ||= BoundSchemaReflection.new(@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.
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 880
def schema_version migration_context.current_version end
#shard
The shard (e.g. :default
) for the current connection. In a non-sharded application, :default
is returned.
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 325
def shard @pool.shard end
#throw_away!
Removes the connection from the pool and disconnect it.
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 749
def throw_away! pool.remove self disconnect! end
#unprepared_statement
[ GitHub ]# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 368
def unprepared_statement cache = prepared_statements_disabled_cache.add?(object_id) if @prepared_statements yield ensure cache&.delete(object_id) 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.
# File 'activerecord/lib/active_record/connection_adapters/abstract_adapter.rb', line 775
def verify! unless active? @lock.synchronize do if @unconfigured_connection @raw_connection = @unconfigured_connection @unconfigured_connection = nil configure_connection @verified = true return end reconnect!(restore_transactions: true) end end @verified = true end