Class: ActiveRecord::ConnectionAdapters::PostgreSQLAdapter

Relationships & Source Files
Super Chains via Extension / Inclusion / Inheritance
Class Chain: self, `AbstractAdapter`, `::ActiveSupport::DescendantsTracker`
Instance Chain: self, `PostgreSQL::DatabaseStatements`, `PostgreSQL::SchemaStatements`, `PostgreSQL::Quoting`, `AbstractAdapter`, `Savepoints`, `::ActiveRecord::QueryCache`, `DatabaseLimits`, `Quoting`, `DatabaseStatements`, `SchemaStatements`, `::ActiveSupport::Callbacks`
Inherits:	ActiveRecord::ConnectionAdapters::AbstractAdapter `::Object` ActiveRecord::ConnectionAdapters::AbstractAdapter ActiveRecord::ConnectionAdapters::PostgreSQLAdapter
Defined in:	activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb

Overview

The PostgreSQL adapter works with the native C (bitbucket.org/ged/ruby-pg) driver.

Options:

:host - Defaults to a Unix-domain socket in /tmp. On machines without Unix-domain sockets, the default is to connect to localhost.
:port - Defaults to 5432.
:username - Defaults to be the same as the operating system name of the user running the application.
:password - Password to be used if the server demands password authentication.
:database - Defaults to be the same as the user name.
:schema_search_path - An optional schema search path for the connection given as a string of comma-separated schema names. This is backward-compatible with the :schema_order option.
:encoding - An optional client encoding that is used in a SET client_encoding TO <encoding> call on the connection.
:min_messages - An optional client min messages that is used in a SET client_min_messages TO <min_messages> call on the connection.
:variables - An optional hash of additional parameters that will be used in SET SESSION key = val calls on the connection.
:insert_returning - An optional boolean to control the use of RETURNING for INSERT statements defaults to true.

Any further options are used as connection parameters to libpq. See www.postgresql.org/docs/current/static/libpq-connect.html for the list of parameters.

In addition, default connection parameters of libpq can be set per environment variables. See www.postgresql.org/docs/current/static/libpq-envars.html .

Constant Summary

ADAPTER_NAME =
# File 'activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb', line 81
```
"PostgreSQL".freeze
```
CACHED_PLAN_HEURISTIC =

Annoyingly, the code for prepared statements whose return value may have changed is FEATURE_NOT_SUPPORTED.

This covers various different error types so we need to do additional work to classify the exception definitively as a ::ActiveRecord::PreparedStatementCacheExpired

Check here for more details: git.postgresql.org/gitweb/?p=postgresql.git;a=blob;f=src/backend/utils/cache/plancache.c#l573

# File 'activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb', line 650
```
"cached plan must not change result type".freeze
```
DEADLOCK_DETECTED =
# File 'activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb', line 416
```
"40P01"
```
FOREIGN_KEY_VIOLATION =
# File 'activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb', line 413
```
"23503"
```
LOCK_NOT_AVAILABLE =
# File 'activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb', line 417
```
"55P03"
```

NATIVE_DATABASE_TYPES =
# File 'activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb', line 83

{
  primary_key: "bigserial primary key",
  string:      { name: "character varying" },
  text:        { name: "text" },
  integer:     { name: "integer", limit: 4 },
  float:       { name: "float" },
  decimal:     { name: "decimal" },
  datetime:    { name: "timestamp" },
  time:        { name: "time" },
  date:        { name: "date" },
  daterange:   { name: "daterange" },
  numrange:    { name: "numrange" },
  tsrange:     { name: "tsrange" },
  tstzrange:   { name: "tstzrange" },
  int4range:   { name: "int4range" },
  int8range:   { name: "int8range" },
  binary:      { name: "bytea" },
  boolean:     { name: "boolean" },
  xml:         { name: "xml" },
  tsvector:    { name: "tsvector" },
  hstore:      { name: "hstore" },
  inet:        { name: "inet" },
  cidr:        { name: "cidr" },
  macaddr:     { name: "macaddr" },
  uuid:        { name: "uuid" },
  json:        { name: "json" },
  jsonb:       { name: "jsonb" },
  ltree:       { name: "ltree" },
  citext:      { name: "citext" },
  point:       { name: "point" },
  line:        { name: "line" },
  lseg:        { name: "lseg" },
  box:         { name: "box" },
  path:        { name: "path" },
  polygon:     { name: "polygon" },
  circle:      { name: "circle" },
  bit:         { name: "bit" },
  bit_varying: { name: "bit varying" },
  money:       { name: "money" },
  interval:    { name: "interval" },
  oid:         { name: "oid" },
}

NOT_NULL_VIOLATION =
# File 'activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb', line 412
```
"23502"
```
NUMERIC_VALUE_OUT_OF_RANGE =
# File 'activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb', line 411
```
"22003"
```
QUERY_CANCELED =
# File 'activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb', line 418
```
"57014"
```
SERIALIZATION_FAILURE =
# File 'activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb', line 415
```
"40001"
```
UNIQUE_VIOLATION =
# File 'activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb', line 414
```
"23505"
```
VALUE_LIMIT_VIOLATION =

See www.postgresql.org/docs/current/static/errcodes-appendix.html

# File 'activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb', line 410
```
"22001"
```

`::ActiveSupport::Callbacks` - Included

CALLBACK_FILTER_TYPES

`AbstractAdapter` - Inherited

ADAPTER_NAME, SIMPLE_INT

Class Attribute Summary

`AbstractAdapter` - Inherited

.__callbacks, .__callbacks?

Class Method Summary

.new(connection, logger, connection_parameters, config) ⇒ PostgreSQLAdapter constructor

Initializes and connects a PostgreSQL adapter.

`AbstractAdapter` - Inherited

.type_cast_config_to_boolean, .type_cast_config_to_integer

`::ActiveSupport::DescendantsTracker` - Inherited

clear, descendants, direct_descendants,
store_inherited	This is the only method that is not thread safe, but is only ever called during the eager loading phase.

Instance Attribute Summary

#active? ⇒ Boolean readonly

Is this connection alive and ready for queries?
#session_auth=(user) writeonly

Set the authorized user for this session.
#supports_advisory_locks? ⇒ Boolean readonly
#supports_bulk_alter? ⇒ Boolean readonly
#supports_comments? ⇒ Boolean readonly
#supports_datetime_with_precision? ⇒ Boolean readonly
#supports_ddl_transactions? ⇒ Boolean readonly
#supports_explain? ⇒ Boolean readonly
#supports_expression_index? ⇒ Boolean readonly
#supports_extensions? ⇒ Boolean readonly
#supports_foreign_keys? ⇒ Boolean readonly
#supports_foreign_tables? ⇒ Boolean readonly
#supports_index_sort_order? ⇒ Boolean readonly
#supports_json? ⇒ Boolean readonly
#supports_materialized_views? ⇒ Boolean readonly
#supports_partial_index? ⇒ Boolean readonly
#supports_pgcrypto_uuid? ⇒ Boolean readonly
#supports_ranges? ⇒ Boolean readonly
#supports_savepoints? ⇒ Boolean readonly
#supports_transaction_isolation? ⇒ Boolean readonly
#supports_validate_constraints? ⇒ Boolean readonly
#supports_views? ⇒ Boolean readonly
#use_insert_returning? ⇒ Boolean readonly

`PostgreSQL::SchemaStatements` - Included

#client_min_messages	Returns the current client message level.
#client_min_messages=	Set the client message level.
#schema_search_path	Returns the active schema search path.
#schema_search_path=	Sets the schema search path to a string of comma-separated schema names.

`AbstractAdapter` - Inherited

#__callbacks, #__callbacks?,
#active?	Checks whether the connection to the database is still active.
#in_use?	Alias for AbstractAdapter#owner.
#lock, #logger, #owner, #pool, #prepared_statements,
#requires_reloading?	Returns true if its required to reload the connection between requests for development mode.
#schema_cache, #schema_cache=,
#supports_advisory_locks?	Does this adapter support application-enforced advisory locking?
#supports_bulk_alter?,
#supports_comments?	Does this adapter support metadata comments on database objects (tables, columns, indexes)?
#supports_comments_in_create?	Can comments for tables, columns, and indexes be specified in create/alter table statements?
#supports_datetime_with_precision?	Does this adapter support datetime with precision?
#supports_ddl_transactions?	Does this adapter support DDL rollbacks in transactions? That is, would CREATE TABLE or ALTER TABLE get rolled back by a transaction?
#supports_explain?	Does this adapter support explain?
#supports_expression_index?	Does this adapter support expression indices?
#supports_extensions?	Does this adapter support database extensions?
#supports_foreign_keys?	Does this adapter support creating foreign key constraints?
#supports_foreign_keys_in_create?	Does this adapter support creating foreign key constraints in the same statement as creating the table?
#supports_foreign_tables?	Does this adapter support foreign/external tables?
#supports_index_sort_order?	Does this adapter support index sort order?
#supports_indexes_in_create?	Does this adapter support creating indexes in the same statement as creating the table?
#supports_json?	Does this adapter support json data type?
#supports_multi_insert?	Does this adapter support multi-value insert?
#supports_partial_index?	Does this adapter support partial indices?
#supports_savepoints?	Does this adapter support savepoints?
#supports_transaction_isolation?	Does this adapter support setting the isolation level for a transaction?
#supports_validate_constraints?	Does this adapter support creating invalid constraints?
#supports_views?	Does this adapter support views?
#supports_virtual_columns?	Does this adapter support virtual columns?
#visitor

`DatabaseStatements` - Included

#begin_transaction, #commit_transaction, #current_transaction, #open_transactions, #rollback_transaction, #transaction_open?, #within_new_transaction

Instance Method Summary

#clear_cache!

Clears the prepared statements cache.
#disable_extension(name)
#disconnect!

Disconnects from the database if already connected.
#enable_extension(name)
#extension_enabled?(name) ⇒ Boolean
#extensions
#index_algorithms
#index_name_length

Alias for #max_identifier_length.
#max_identifier_length (also: #table_alias_length, #index_name_length)

Returns the configured supported identifier length supported by PostgreSQL.
#postgresql_version

Returns the version of the connected PostgreSQL server.
#reconnect!

Close then reopen the connection.
#reset!
#set_standard_conforming_strings
#table_alias_length

Alias for #max_identifier_length.
#truncate(table_name, name = nil)

`PostgreSQL::DatabaseStatements` - Included

#begin_db_transaction	Begins a transaction.
#begin_isolated_db_transaction,
#commit_db_transaction	Commits a transaction.
#exec_delete, #exec_insert, #exec_query,
#exec_rollback_db_transaction	Aborts a transaction.
#exec_update	Alias for PostgreSQL::DatabaseStatements#exec_delete.
#execute	Executes an SQL statement, returning a `PG::Result` object on success or raising a `PG::Error` exception otherwise.
#explain

`PostgreSQL::SchemaStatements` - Included

#bulk_change_table,
#collation	Returns the current database collation.
#create_database	Create a new `PostgreSQL` database.
#create_schema	Creates a schema for the given schema name.
#ctype	Returns the current database ctype.
#current_database	Returns the current database name.
#current_schema	Returns the current schema name.
#drop_schema	Drops the schema for the given schema name.
#encoding	Returns the current database encoding format.
#foreign_keys, #foreign_table_exists?, #foreign_tables,
#index_name_exists?	Verifies existence of an index with a given name.
#rename_index	Renames an index of a table.
#rename_table	Renames a table.
#schema_exists?	Returns true if schema exists.
#schema_names	Returns an array of schema names.
#serial_sequence,
#validate_constraint	Validates the given constraint.
#validate_foreign_key	Validates the given foreign key.

`PostgreSQL::Quoting` - Included

#escape_bytea	Escapes binary strings for bytea input to the database.
#quote_schema_name	Quotes schema names for use in SQL queries.
#quote_table_name_for_assignment,
#unescape_bytea	Unescapes bytea output from a database to the binary string it represents.

`AbstractAdapter` - Inherited

#adapter_name	Returns the human-readable name of the adapter.
#clear_cache!	Clear any caching the database adapter may be doing, for example clearing the prepared statement cache.
#close	Check the connection back in to the connection pool.
#disable_extension	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	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?	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.
#raw_connection	Provides access to the underlying database driver for this adapter.
#reconnect!	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.
#unprepared_statement,
#verify!	Checks whether the connection to the database is still active (i.e. not stale).
#log

`Savepoints` - Included

#create_savepoint, #current_savepoint_name, #exec_rollback_to_savepoint, #release_savepoint

`DatabaseLimits` - Included

#allowed_index_name_length	Returns the maximum allowed length for an index name.
#column_name_length	Returns the maximum length of a column name.
#columns_per_multicolumn_index	Returns the maximum number of columns in a multicolumn index.
#columns_per_table	Returns the maximum number of columns per table.
#in_clause_length	Returns the maximum number of elements in an IN (x,y,z) clause.
#index_name_length	Returns the maximum length of an index name.
#indexes_per_table	Returns the maximum number of indexes per table.
#joins_per_query	Returns maximum number of joins in a single query.
#sql_query_length	Returns the maximum length of an SQL query.
#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_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

`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.
#empty_insert_statement_value,
#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.
#initialize,
#insert	Executes an INSERT query and returns the new record’s ID.
#insert_fixture	Inserts the given fixture into the table.
#insert_fixtures	Inserts a set of fixtures into the table.
#insert_fixtures_set,
#join_to_delete	Alias for DatabaseStatements#join_to_update.
#reset_sequence!	Set the sequence to the max value of the table’s column.
#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 `::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, #transaction_state,
#truncate	Executes the truncate statement.
#update	Executes the update statement and returns the number of rows affected.

`SchemaStatements` - Included

#add_belongs_to	Alias for SchemaStatements#add_reference.
#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,
#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`.
#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 useable 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.
#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_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.

`::ActiveSupport::Callbacks` - Included

#run_callbacks

Runs the callbacks for the given event.

Constructor Details

.new(connection, logger, connection_parameters, config) ⇒ `PostgreSQLAdapter`

Initializes and connects a PostgreSQL adapter.

[ GitHub ]

# File 'activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb', line 214


def initialize(connection, logger, connection_parameters, config)
  super(connection, logger, config)

  @connection_parameters = connection_parameters

  # @local_tz is initialized as nil to avoid warnings when connect tries to use it
  @local_tz = nil
  @max_identifier_length = nil

  connect
  add_pg_encoders
  @statements = StatementPool.new @connection,
                                  self.class.type_cast_config_to_integer(config[:statement_limit])

  if postgresql_version < 90100
    raise "Your version of PostgreSQL (#{postgresql_version}) is too old. Active Record supports PostgreSQL >= 9.1."
  end

  add_pg_decoders

  @type_map = Type::HashLookupTypeMap.new
  initialize_type_map
  @local_tz = execute("SHOW TIME ZONE", "SCHEMA").first["TimeZone"]
  @use_insert_returning = @config.key?(:insert_returning) ? self.class.type_cast_config_to_boolean(@config[:insert_returning]) : true
end

Instance Attribute Details

#active? ⇒ `Boolean` (readonly)

Is this connection alive and ready for queries?

[ GitHub ]

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


def active?
  @lock.synchronize do
    @connection.query "SELECT 1"
  end
  true
rescue PG::Error
  false
end

#session_auth=(user) (writeonly)

Set the authorized user for this session

[ GitHub ]

# File 'activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb', line 380


def session_auth=(user)
  clear_cache!
  execute("SET SESSION AUTHORIZATION #{user}")
end

#supports_advisory_locks? ⇒ `Boolean` (readonly)

[ GitHub ]

# File 'activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb', line 308


def supports_advisory_locks?
  true
end

#supports_bulk_alter? ⇒ `Boolean` (readonly)

[ GitHub ]

# File 'activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb', line 133


def supports_bulk_alter?
  true
end

#supports_comments? ⇒ `Boolean` (readonly)

[ GitHub ]

# File 'activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb', line 173


def supports_comments?
  true
end

#supports_datetime_with_precision? ⇒ `Boolean` (readonly)

[ GitHub ]

# File 'activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb', line 165


def supports_datetime_with_precision?
  true
end

#supports_ddl_transactions? ⇒ `Boolean` (readonly)

[ GitHub ]

# File 'activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb', line 304


def supports_ddl_transactions?
  true
end

#supports_explain? ⇒ `Boolean` (readonly)

[ GitHub ]

# File 'activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb', line 312


def supports_explain?
  true
end

#supports_expression_index? ⇒ `Boolean` (readonly)

[ GitHub ]

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


def supports_expression_index?
  true
end

#supports_extensions? ⇒ `Boolean` (readonly)

[ GitHub ]

# File 'activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb', line 316


def supports_extensions?
  true
end

#supports_foreign_keys? ⇒ `Boolean` (readonly)

[ GitHub ]

# File 'activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb', line 153


def supports_foreign_keys?
  true
end

#supports_foreign_tables? ⇒ `Boolean` (readonly)

[ GitHub ]

# File 'activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb', line 329


def supports_foreign_tables?
  postgresql_version >= 90300
end

#supports_index_sort_order? ⇒ `Boolean` (readonly)

[ GitHub ]

# File 'activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb', line 137


def supports_index_sort_order?
  true
end

#supports_json? ⇒ `Boolean` (readonly)

[ GitHub ]

# File 'activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb', line 169


def supports_json?
  postgresql_version >= 90200
end

#supports_materialized_views? ⇒ `Boolean` (readonly)

[ GitHub ]

# File 'activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb', line 325


def supports_materialized_views?
  postgresql_version >= 90300
end

#supports_partial_index? ⇒ `Boolean` (readonly)

[ GitHub ]

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


def supports_partial_index?
  true
end

#supports_pgcrypto_uuid? ⇒ `Boolean` (readonly)

[ GitHub ]

# File 'activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb', line 333


def supports_pgcrypto_uuid?
  postgresql_version >= 90400
end

#supports_ranges? ⇒ `Boolean` (readonly)

[ GitHub ]

# File 'activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb', line 320


def supports_ranges?
  # Range datatypes weren't introduced until PostgreSQL 9.2
  postgresql_version >= 90200
end

#supports_savepoints? ⇒ `Boolean` (readonly)

[ GitHub ]

# File 'activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb', line 177


def supports_savepoints?
  true
end

#supports_transaction_isolation? ⇒ `Boolean` (readonly)

[ GitHub ]

# File 'activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb', line 149


def supports_transaction_isolation?
  true
end

#supports_validate_constraints? ⇒ `Boolean` (readonly)

[ GitHub ]

# File 'activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb', line 157


def supports_validate_constraints?
  true
end

#supports_views? ⇒ `Boolean` (readonly)

[ GitHub ]

# File 'activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb', line 161


def supports_views?
  true
end

#use_insert_returning? ⇒ `Boolean` (readonly)

[ GitHub ]

# File 'activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb', line 385


def use_insert_returning?
  @use_insert_returning
end

Instance Method Details

#clear_cache!

Clears the prepared statements cache.

[ GitHub ]

# File 'activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb', line 241


def clear_cache!
  @lock.synchronize do
    @statements.clear
  end
end

#disable_extension(name)

[ GitHub ]

# File 'activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb', line 357


def disable_extension(name)
  exec_query("DROP EXTENSION IF EXISTS \"#{name}\" CASCADE").tap {
    reload_type_map
  }
end

#disconnect!

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

[ GitHub ]

# File 'activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb', line 284


def disconnect!
  @lock.synchronize do
    super
    @connection.close rescue nil
  end
end

#enable_extension(name)

[ GitHub ]

# File 'activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb', line 351


def enable_extension(name)
  exec_query("CREATE EXTENSION IF NOT EXISTS \"#{name}\"").tap {
    reload_type_map
  }
end

#extension_enabled?(name) ⇒ `Boolean`

[ GitHub ]

# File 'activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb', line 363


def extension_enabled?(name)
  res = exec_query("SELECT EXISTS(SELECT * FROM pg_available_extensions WHERE name = '#{name}' AND installed_version IS NOT NULL) as enabled", "SCHEMA")
  res.cast_values.first
end

#extensions

[ GitHub ]

# File 'activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb', line 368


def extensions
  exec_query("SELECT extname FROM pg_extension", "SCHEMA").cast_values
end

#index_algorithms

[ GitHub ]

# File 'activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb', line 181


def index_algorithms
  { concurrently: "CONCURRENTLY" }
end

#index_name_length

Alias for #max_identifier_length.

[ GitHub ]

# File 'activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb', line 377


alias index_name_length max_identifier_length

#max_identifier_length Also known as: #table_alias_length, #index_name_length

Returns the configured supported identifier length supported by PostgreSQL

[ GitHub ]

# File 'activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb', line 373


def max_identifier_length
  @max_identifier_length ||= query_value("SHOW max_identifier_length", "SCHEMA").to_i
end

#postgresql_version

Returns the version of the connected PostgreSQL server.

[ GitHub ]

# File 'activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb', line 400


def postgresql_version
  @connection.server_version
end

#reconnect!

Close then reopen the connection.

[ GitHub ]

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


def reconnect!
  @lock.synchronize do
    super
    @connection.reset
    configure_connection
  end
end

#reset!

[ GitHub ]

# File 'activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb', line 270


def reset!
  @lock.synchronize do
    clear_cache!
    reset_transaction
    unless @connection.transaction_status == ::PG::PQTRANS_IDLE
      @connection.query "ROLLBACK"
    end
    @connection.query "DISCARD ALL"
    configure_connection
  end
end

#set_standard_conforming_strings

[ GitHub ]

# File 'activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb', line 300


def set_standard_conforming_strings
  execute("SET standard_conforming_strings = on", "SCHEMA")
end

#table_alias_length

Alias for #max_identifier_length.

[ GitHub ]

# File 'activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb', line 376


alias table_alias_length max_identifier_length

#truncate(table_name, name = nil)

[ GitHub ]

# File 'activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb', line 247


def truncate(table_name, name = nil)
  exec_query "TRUNCATE TABLE #{quote_table_name(table_name)}", name, []
end

Class: ActiveRecord::ConnectionAdapters::PostgreSQLAdapter

Overview

Constant Summary

::ActiveSupport::Callbacks - Included

AbstractAdapter - Inherited

Class Attribute Summary

AbstractAdapter - Inherited

Class Method Summary

AbstractAdapter - Inherited

::ActiveSupport::DescendantsTracker - Inherited

Instance Attribute Summary

PostgreSQL::SchemaStatements - Included

AbstractAdapter - Inherited

DatabaseStatements - Included

Instance Method Summary

PostgreSQL::DatabaseStatements - Included

PostgreSQL::SchemaStatements - Included

PostgreSQL::Quoting - Included

AbstractAdapter - Inherited

Savepoints - Included

DatabaseLimits - Included

Quoting - Included

DatabaseStatements - Included

SchemaStatements - Included

::ActiveSupport::Callbacks - Included

Constructor Details

.new(connection, logger, connection_parameters, config) ⇒ PostgreSQLAdapter

Instance Attribute Details

#active? ⇒ Boolean (readonly)

#session_auth=(user) (writeonly)

#supports_advisory_locks? ⇒ Boolean (readonly)

#supports_bulk_alter? ⇒ Boolean (readonly)

#supports_comments? ⇒ Boolean (readonly)

#supports_datetime_with_precision? ⇒ Boolean (readonly)

#supports_ddl_transactions? ⇒ Boolean (readonly)

#supports_explain? ⇒ Boolean (readonly)

#supports_expression_index? ⇒ Boolean (readonly)

#supports_extensions? ⇒ Boolean (readonly)

#supports_foreign_keys? ⇒ Boolean (readonly)

#supports_foreign_tables? ⇒ Boolean (readonly)

#supports_index_sort_order? ⇒ Boolean (readonly)

#supports_json? ⇒ Boolean (readonly)

#supports_materialized_views? ⇒ Boolean (readonly)

#supports_partial_index? ⇒ Boolean (readonly)

#supports_pgcrypto_uuid? ⇒ Boolean (readonly)

#supports_ranges? ⇒ Boolean (readonly)

#supports_savepoints? ⇒ Boolean (readonly)

#supports_transaction_isolation? ⇒ Boolean (readonly)

#supports_validate_constraints? ⇒ Boolean (readonly)

#supports_views? ⇒ Boolean (readonly)

#use_insert_returning? ⇒ Boolean (readonly)

Instance Method Details

#clear_cache!

#disable_extension(name)

#disconnect!

#enable_extension(name)

#extension_enabled?(name) ⇒ Boolean

#extensions

#index_algorithms

#index_name_length

#max_identifier_length Also known as: #table_alias_length, #index_name_length

#postgresql_version

#reconnect!

#reset!

#set_standard_conforming_strings

#table_alias_length

#truncate(table_name, name = nil)

`::ActiveSupport::Callbacks` - Included

`AbstractAdapter` - Inherited

`AbstractAdapter` - Inherited

`AbstractAdapter` - Inherited

`::ActiveSupport::DescendantsTracker` - Inherited

`PostgreSQL::SchemaStatements` - Included

`AbstractAdapter` - Inherited

`DatabaseStatements` - Included

`PostgreSQL::DatabaseStatements` - Included

`PostgreSQL::SchemaStatements` - Included

`PostgreSQL::Quoting` - Included

`AbstractAdapter` - Inherited

`Savepoints` - Included

`DatabaseLimits` - Included

`Quoting` - Included

`DatabaseStatements` - Included

`SchemaStatements` - Included

`::ActiveSupport::Callbacks` - Included

.new(connection, logger, connection_parameters, config) ⇒ `PostgreSQLAdapter`

#active? ⇒ `Boolean` (readonly)

#supports_advisory_locks? ⇒ `Boolean` (readonly)

#supports_bulk_alter? ⇒ `Boolean` (readonly)

#supports_comments? ⇒ `Boolean` (readonly)

#supports_datetime_with_precision? ⇒ `Boolean` (readonly)

#supports_ddl_transactions? ⇒ `Boolean` (readonly)

#supports_explain? ⇒ `Boolean` (readonly)

#supports_expression_index? ⇒ `Boolean` (readonly)

#supports_extensions? ⇒ `Boolean` (readonly)

#supports_foreign_keys? ⇒ `Boolean` (readonly)

#supports_foreign_tables? ⇒ `Boolean` (readonly)

#supports_index_sort_order? ⇒ `Boolean` (readonly)

#supports_json? ⇒ `Boolean` (readonly)

#supports_materialized_views? ⇒ `Boolean` (readonly)

#supports_partial_index? ⇒ `Boolean` (readonly)

#supports_pgcrypto_uuid? ⇒ `Boolean` (readonly)

#supports_ranges? ⇒ `Boolean` (readonly)

#supports_savepoints? ⇒ `Boolean` (readonly)

#supports_transaction_isolation? ⇒ `Boolean` (readonly)

#supports_validate_constraints? ⇒ `Boolean` (readonly)

#supports_views? ⇒ `Boolean` (readonly)

#use_insert_returning? ⇒ `Boolean` (readonly)

#extension_enabled?(name) ⇒ `Boolean`