Class: ActiveRecord::ConnectionAdapters::PostgreSQLAdapter

Overview

The PostgreSQL adapter works with the native C (github.com/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 username.

  • :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 .

Defined Under Namespace

Classes: MoneyDecoder, StatementPool

Constant Summary collapse

ADAPTER_NAME =
"PostgreSQL"
NATIVE_DATABASE_TYPES =
{
  primary_key: "bigserial primary key",
  string:      { name: "character varying" },
  text:        { name: "text" },
  integer:     { name: "integer", limit: 4 },
  bigint:      { name: "bigint" },
  float:       { name: "float" },
  decimal:     { name: "decimal" },
  datetime:    {}, # set dynamically based on datetime_type
  timestamp:   { name: "timestamp" },
  timestamptz: { name: "timestamptz" },
  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" },
  enum:        {} # special type https://www.postgresql.org/docs/current/datatype-enum.html
}
OID =

:nodoc:

PostgreSQL::OID

Constants inherited from AbstractAdapter

AbstractAdapter::COMMENT_REGEX, AbstractAdapter::SIMPLE_INT, AbstractAdapter::TYPE_MAP

Instance Attribute Summary

Attributes inherited from AbstractAdapter

#lock, #logger, #owner, #pool, #visitor

Attributes included from QueryCache

#query_cache, #query_cache_enabled

Attributes included from DatabaseStatements

#transaction_manager

Class Method Summary collapse

Instance Method Summary collapse

Methods included from ActiveRecord::ConnectionAdapters::PostgreSQL::DatabaseStatements

#begin_db_transaction, #begin_isolated_db_transaction, #commit_db_transaction, #exec_delete, #exec_insert, #exec_query, #exec_rollback_db_transaction, #execute, #explain, #high_precision_current_timestamp, #query, #write_query?

Methods included from ActiveRecord::ConnectionAdapters::PostgreSQL::SchemaStatements

#add_column, #add_index, #change_column, #change_column_comment, #change_column_default, #change_column_null, #change_table_comment, #check_constraints, #client_min_messages, #client_min_messages=, #collation, #columns_for_distinct, #create_database, #create_schema, #create_schema_dumper, #ctype, #current_database, #current_schema, #default_sequence_name, #drop_database, #drop_schema, #drop_table, #encoding, #foreign_keys, #foreign_table_exists?, #foreign_tables, #index_name_exists?, #indexes, #pk_and_sequence_for, #primary_keys, #recreate_database, #remove_index, #rename_column, #rename_index, #rename_table, #reset_pk_sequence!, #schema_exists?, #schema_names, #schema_search_path, #schema_search_path=, #serial_sequence, #set_pk_sequence!, #table_comment, #table_options, #type_to_sql, #update_table_definition, #validate_check_constraint, #validate_constraint, #validate_foreign_key

Methods included from ActiveRecord::ConnectionAdapters::PostgreSQL::ReferentialIntegrity

#all_foreign_keys_valid?, #disable_referential_integrity

Methods included from ActiveRecord::ConnectionAdapters::PostgreSQL::Quoting

#column_name_matcher, #column_name_with_order_matcher, #escape_bytea, #lookup_cast_type_from_column, #quote, #quote_column_name, #quote_default_expression, #quote_schema_name, #quote_string, #quote_table_name, #quote_table_name_for_assignment, #quoted_binary, #quoted_date, #type_cast, #unescape_bytea

Methods inherited from AbstractAdapter

#adapter_name, #advisory_locks_enabled?, #all_foreign_keys_valid?, #async_enabled?, build_read_query_regexp, #case_insensitive_comparison, #case_sensitive_comparison, #check_if_write_query, #clear_cache!, #close, #connection_class, #database_version, #default_uniqueness_comparison, #disable_referential_integrity, #expire, #field_ordered_value, #lease, #migration_context, #migrations_paths, #prefetch_primary_key?, #prepared_statements?, #prepared_statements_disabled_cache, #preventing_writes?, quoted_column_names, quoted_table_names, #raw_connection, #replica?, #requires_reloading?, #role, #schema_cache, #schema_cache=, #schema_migration, #schema_version, #seconds_idle, #shard, #steal!, #supports_comments_in_create?, #supports_concurrent_connections?, #supports_indexes_in_create?, #throw_away!, type_cast_config_to_boolean, type_cast_config_to_integer, #unprepared_statement, #use_metadata_table?, #valid_type?, #verify!, #with_instrumenter

Methods included from Savepoints

#create_savepoint, #current_savepoint_name, #exec_rollback_to_savepoint, #release_savepoint

Methods included from QueryCache

#cache, #clear_query_cache, dirties_query_cache, #disable_query_cache!, #enable_query_cache!, included, #select_all, #uncached

Methods included from DatabaseLimits

#index_name_length, #table_alias_length

Methods included from Quoting

#column_name_matcher, #column_name_with_order_matcher, #lookup_cast_type_from_column, #quote, #quote_bound_value, #quote_column_name, #quote_default_expression, #quote_string, #quote_table_name, #quote_table_name_for_assignment, #quoted_binary, #quoted_date, #quoted_false, #quoted_time, #quoted_true, #sanitize_as_sql_comment, #type_cast, #unquoted_false, #unquoted_true

Methods included from DatabaseStatements

#add_transaction_record, #begin_db_transaction, #begin_isolated_db_transaction, #cacheable_query, #commit_db_transaction, #default_sequence_name, #delete, #empty_insert_statement_value, #exec_delete, #exec_insert, #exec_insert_all, #exec_query, #exec_rollback_db_transaction, #exec_update, #execute, #explain, #high_precision_current_timestamp, #insert, #insert_fixture, #insert_fixtures_set, #mark_transaction_written_if_write, #query, #query_value, #query_values, #reset_sequence!, #reset_transaction, #rollback_db_transaction, #rollback_to_savepoint, #sanitize_limit, #select_all, #select_one, #select_rows, #select_value, #select_values, #to_sql, #transaction, #transaction_isolation_levels, #transaction_open?, #truncate, #truncate_tables, #update, #with_yaml_fallback, #write_query?

Methods included from SchemaStatements

#add_check_constraint, #add_column, #add_columns, #add_foreign_key, #add_index, #add_index_options, #add_reference, #add_timestamps, #assume_migrated_upto_version, #change_column, #change_column_comment, #change_column_default, #change_column_null, #change_table, #change_table_comment, #check_constraint_options, #check_constraints, #column_exists?, #columns, #columns_for_distinct, #create_join_table, #create_schema_dumper, #create_table, #data_source_exists?, #data_sources, #distinct_relation_for_primary_key, #drop_join_table, #drop_table, #dump_schema_information, #foreign_key_column_for, #foreign_key_exists?, #foreign_key_options, #foreign_keys, #index_algorithm, #index_exists?, #index_name, #index_name_exists?, #indexes, #internal_string_options_for_primary_key, #options_include_default?, #primary_key, #quoted_columns_for_index, #remove_check_constraint, #remove_column, #remove_columns, #remove_foreign_key, #remove_index, #remove_reference, #remove_timestamps, #rename_column, #rename_index, #rename_table, #table_alias_for, #table_comment, #table_exists?, #table_options, #tables, #type_to_sql, #update_table_definition, #view_exists?, #views

Constructor Details

#initialize(connection, logger, connection_parameters, config) ⇒ PostgreSQLAdapter

Initializes and connects a PostgreSQL adapter.


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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 281

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

  configure_connection
  add_pg_encoders
  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

Class Method Details

.database_exists?(config) ⇒ Boolean

Returns:

  • (Boolean)

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

def self.database_exists?(config)
  !!ActiveRecord::Base.postgresql_connection(config)
rescue ActiveRecord::NoDatabaseError
  false
end

.initialize_type_map(m) ⇒ Object

:nodoc:


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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 540

def initialize_type_map(m) # :nodoc:
  m.register_type "int2", Type::Integer.new(limit: 2)
  m.register_type "int4", Type::Integer.new(limit: 4)
  m.register_type "int8", Type::Integer.new(limit: 8)
  m.register_type "oid", OID::Oid.new
  m.register_type "float4", Type::Float.new
  m.alias_type "float8", "float4"
  m.register_type "text", Type::Text.new
  register_class_with_limit m, "varchar", Type::String
  m.alias_type "char", "varchar"
  m.alias_type "name", "varchar"
  m.alias_type "bpchar", "varchar"
  m.register_type "bool", Type::Boolean.new
  register_class_with_limit m, "bit", OID::Bit
  register_class_with_limit m, "varbit", OID::BitVarying
  m.register_type "date", OID::Date.new

  m.register_type "money", OID::Money.new
  m.register_type "bytea", OID::Bytea.new
  m.register_type "point", OID::Point.new
  m.register_type "hstore", OID::Hstore.new
  m.register_type "json", Type::Json.new
  m.register_type "jsonb", OID::Jsonb.new
  m.register_type "cidr", OID::Cidr.new
  m.register_type "inet", OID::Inet.new
  m.register_type "uuid", OID::Uuid.new
  m.register_type "xml", OID::Xml.new
  m.register_type "tsvector", OID::SpecializedString.new(:tsvector)
  m.register_type "macaddr", OID::Macaddr.new
  m.register_type "citext", OID::SpecializedString.new(:citext)
  m.register_type "ltree", OID::SpecializedString.new(:ltree)
  m.register_type "line", OID::SpecializedString.new(:line)
  m.register_type "lseg", OID::SpecializedString.new(:lseg)
  m.register_type "box", OID::SpecializedString.new(:box)
  m.register_type "path", OID::SpecializedString.new(:path)
  m.register_type "polygon", OID::SpecializedString.new(:polygon)
  m.register_type "circle", OID::SpecializedString.new(:circle)

  register_class_with_precision m, "time", Type::Time
  register_class_with_precision m, "timestamp", OID::Timestamp
  register_class_with_precision m, "timestamptz", OID::TimestampWithTimeZone

  m.register_type "numeric" do |_, fmod, sql_type|
    precision = extract_precision(sql_type)
    scale = extract_scale(sql_type)

    # The type for the numeric depends on the width of the field,
    # so we'll do something special here.
    #
    # When dealing with decimal columns:
    #
    # places after decimal  = fmod - 4 & 0xffff
    # places before decimal = (fmod - 4) >> 16 & 0xffff
    if fmod && (fmod - 4 & 0xffff).zero?
      # FIXME: Remove this class, and the second argument to
      # lookups on PG
      Type::DecimalWithoutScale.new(precision: precision)
    else
      OID::Decimal.new(precision: precision, scale: scale)
    end
  end

  m.register_type "interval" do |*args, sql_type|
    precision = extract_precision(sql_type)
    OID::Interval.new(precision: precision)
  end
end

.native_database_typesObject

:nodoc:


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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 364

def self.native_database_types # :nodoc:
  @native_database_types ||= begin
    types = NATIVE_DATABASE_TYPES.dup
    types[:datetime] = types[datetime_type]
    types
  end
end

.new_client(conn_params) ⇒ Object


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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 77

def new_client(conn_params)
  PG.connect(**conn_params)
rescue ::PG::Error => error
  if conn_params && conn_params[:dbname] && error.message.include?(conn_params[:dbname])
    raise ActiveRecord::NoDatabaseError.db_error(conn_params[:dbname])
  elsif conn_params && conn_params[:user] && error.message.include?(conn_params[:user])
    raise ActiveRecord::DatabaseConnectionError.username_error(conn_params[:user])
  elsif conn_params && conn_params[:hostname] && error.message.include?(conn_params[:hostname])
    raise ActiveRecord::DatabaseConnectionError.hostname_error(conn_params[:hostname])
  else
    raise ActiveRecord::ConnectionNotEstablished, error.message
  end
end

Instance Method Details

#active?Boolean

Is this connection alive and ready for queries?

Returns:

  • (Boolean)

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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 307

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

#build_insert_sql(insert) ⇒ Object

:nodoc:


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

def build_insert_sql(insert) # :nodoc:
  sql = +"INSERT #{insert.into} #{insert.values_list}"

  if insert.skip_duplicates?
    sql << " ON CONFLICT #{insert.conflict_target} DO NOTHING"
  elsif insert.update_duplicates?
    sql << " ON CONFLICT #{insert.conflict_target} DO UPDATE SET "
    if insert.raw_update_sql?
      sql << insert.raw_update_sql
    else
      sql << insert.touch_model_timestamps_unless { |column| "#{insert.model.quoted_table_name}.#{column} IS NOT DISTINCT FROM excluded.#{column}" }
      sql << insert.updatable_columns.map { |column| "#{column}=excluded.#{column}" }.join(",")
    end
  end

  sql << " RETURNING #{insert.returning}" if insert.returning
  sql
end

#check_versionObject

:nodoc:


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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 533

def check_version # :nodoc:
  if database_version < 90300 # < 9.3
    raise "Your version of PostgreSQL (#{database_version}) is too old. Active Record supports PostgreSQL >= 9.3."
  end
end

#create_enum(name, values) ⇒ Object

Given a name and an array of values, creates an enum type.


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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 472

def create_enum(name, values)
  sql_values = values.map { |s| "'#{s}'" }.join(", ")
  query = <<~SQL
    DO $$
    BEGIN
        IF NOT EXISTS (
          SELECT 1 FROM pg_type t
          WHERE t.typname = '#{name}'
        ) THEN
            CREATE TYPE \"#{name}\" AS ENUM (#{sql_values});
        END IF;
    END
    $$;
  SQL
  exec_query(query)
end

#create_unlogged_tablesObject

:singleton-method: PostgreSQL allows the creation of “unlogged” tables, which do not record data in the PostgreSQL Write-Ahead Log. This can make the tables faster, but significantly increases the risk of data loss if the database crashes. As a result, this should not be used in production environments. If you would like all created tables to be unlogged in the test environment you can add the following line to your test.rb file:

ActiveRecord::ConnectionAdapters::PostgreSQLAdapter.create_unlogged_tables = true

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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 103

class_attribute :create_unlogged_tables, default: false

#datetime_typeObject

:singleton-method: PostgreSQL supports multiple types for DateTimes. By default, if you use datetime in migrations, Rails will translate this to a PostgreSQL “timestamp without time zone”. Change this in an initializer to use another NATIVE_DATABASE_TYPES. For example, to store DateTimes as “timestamp with time zone”:

ActiveRecord::ConnectionAdapters::PostgreSQLAdapter.datetime_type = :timestamptz

Or if you are adding a custom type:

ActiveRecord::ConnectionAdapters::PostgreSQLAdapter::NATIVE_DATABASE_TYPES[:my_custom_type] = { name: "my_custom_type_name" }
ActiveRecord::ConnectionAdapters::PostgreSQLAdapter.datetime_type = :my_custom_type

If you're using :ruby as your config.active_record.schema_format and you change this setting, you should immediately run bin/rails db:migrate to update the types in your schema.rb.


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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 121

class_attribute :datetime_type, default: :timestamp

#default_index_type?(index) ⇒ Boolean

:nodoc:

Returns:

  • (Boolean)

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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 510

def default_index_type?(index) # :nodoc:
  index.using == :btree || super
end

#disable_extension(name) ⇒ Object


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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 439

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

#discard!Object

:nodoc:


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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 354

def discard! # :nodoc:
  super
  @connection.socket_io.reopen(IO::NULL) rescue nil
  @connection = nil
end

#disconnect!Object

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


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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 347

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

#enable_extension(name) ⇒ Object


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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 433

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

#enum_typesObject

Returns a list of defined enum types, and their values.


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

def enum_types
  query = <<~SQL
    SELECT
      type.typname AS name,
      string_agg(enum.enumlabel, ',' ORDER BY enum.enumsortorder) AS value
    FROM pg_enum AS enum
    JOIN pg_type AS type
      ON (type.oid = enum.enumtypid)
    GROUP BY type.typname;
  SQL
  exec_query(query, "SCHEMA").cast_values
end

#extension_available?(name) ⇒ Boolean

Returns:

  • (Boolean)

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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 445

def extension_available?(name)
  query_value("SELECT true FROM pg_available_extensions WHERE name = #{quote(name)}", "SCHEMA")
end

#extension_enabled?(name) ⇒ Boolean

Returns:

  • (Boolean)

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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 449

def extension_enabled?(name)
  query_value("SELECT installed_version IS NOT NULL FROM pg_available_extensions WHERE name = #{quote(name)}", "SCHEMA")
end

#extensionsObject


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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 453

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

#get_advisory_lock(lock_id) ⇒ Object

:nodoc:


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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 419

def get_advisory_lock(lock_id) # :nodoc:
  unless lock_id.is_a?(Integer) && lock_id.bit_length <= 63
    raise(ArgumentError, "PostgreSQL requires advisory lock ids to be a signed 64 bit integer")
  end
  query_value("SELECT pg_try_advisory_lock(#{lock_id})")
end

#get_database_versionObject

Returns the version of the connected PostgreSQL server.


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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 505

def get_database_version # :nodoc:
  @connection.server_version
end

#index_algorithmsObject


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

def index_algorithms
  { concurrently: "CONCURRENTLY" }
end

#max_identifier_lengthObject

Returns the configured supported identifier length supported by PostgreSQL


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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 490

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

#native_database_typesObject

:nodoc:


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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 360

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

#reconnect!Object

Close then reopen the connection.


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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 322

def reconnect!
  @lock.synchronize do
    super
    @connection.reset
    configure_connection
    reload_type_map
  rescue PG::ConnectionBad
    connect
  end
end

#release_advisory_lock(lock_id) ⇒ Object

:nodoc:


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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 426

def release_advisory_lock(lock_id) # :nodoc:
  unless lock_id.is_a?(Integer) && lock_id.bit_length <= 63
    raise(ArgumentError, "PostgreSQL requires advisory lock ids to be a signed 64 bit integer")
  end
  query_value("SELECT pg_advisory_unlock(#{lock_id})")
end

#reload_type_mapObject

:nodoc:


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

def reload_type_map # :nodoc:
  type_map.clear
  initialize_type_map
end

#reset!Object


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

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

#session_auth=(user) ⇒ Object

Set the authorized user for this session


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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 495

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

#set_standard_conforming_stringsObject


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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 372

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

#supports_advisory_locks?Boolean

Returns:

  • (Boolean)

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

def supports_advisory_locks?
  true
end

#supports_bulk_alter?Boolean

Returns:

  • (Boolean)

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

def supports_bulk_alter?
  true
end

#supports_check_constraints?Boolean

Returns:

  • (Boolean)

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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 205

def supports_check_constraints?
  true
end

#supports_comments?Boolean

Returns:

  • (Boolean)

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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 229

def supports_comments?
  true
end

#supports_common_table_expressions?Boolean

Returns:

  • (Boolean)

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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 411

def supports_common_table_expressions?
  true
end

#supports_datetime_with_precision?Boolean

Returns:

  • (Boolean)

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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 221

def supports_datetime_with_precision?
  true
end

#supports_ddl_transactions?Boolean

Returns:

  • (Boolean)

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

def supports_ddl_transactions?
  true
end

#supports_deferrable_constraints?Boolean

Returns:

  • (Boolean)

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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 213

def supports_deferrable_constraints?
  true
end

#supports_explain?Boolean

Returns:

  • (Boolean)

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

def supports_explain?
  true
end

#supports_expression_index?Boolean

Returns:

  • (Boolean)

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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 193

def supports_expression_index?
  true
end

#supports_extensions?Boolean

Returns:

  • (Boolean)

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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 388

def supports_extensions?
  true
end

#supports_foreign_keys?Boolean

Returns:

  • (Boolean)

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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 201

def supports_foreign_keys?
  true
end

#supports_foreign_tables?Boolean

Returns:

  • (Boolean)

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

def supports_foreign_tables?
  true
end

#supports_index_sort_order?Boolean

Returns:

  • (Boolean)

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

def supports_index_sort_order?
  true
end

#supports_insert_on_conflict?Boolean Also known as: supports_insert_on_duplicate_skip?, supports_insert_on_duplicate_update?, supports_insert_conflict_target?

Returns:

  • (Boolean)

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

def supports_insert_on_conflict?
  database_version >= 90500 # >= 9.5
end

#supports_insert_returning?Boolean

Returns:

  • (Boolean)

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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 237

def supports_insert_returning?
  true
end

#supports_json?Boolean

Returns:

  • (Boolean)

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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 225

def supports_json?
  true
end

#supports_lazy_transactions?Boolean

Returns:

  • (Boolean)

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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 415

def supports_lazy_transactions?
  true
end

#supports_materialized_views?Boolean

Returns:

  • (Boolean)

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

def supports_materialized_views?
  true
end

#supports_optimizer_hints?Boolean

Returns:

  • (Boolean)

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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 404

def supports_optimizer_hints?
  unless defined?(@has_pg_hint_plan)
    @has_pg_hint_plan = extension_available?("pg_hint_plan")
  end
  @has_pg_hint_plan
end

#supports_partial_index?Boolean

Returns:

  • (Boolean)

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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 189

def supports_partial_index?
  true
end

#supports_partitioned_indexes?Boolean

Returns:

  • (Boolean)

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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 185

def supports_partitioned_indexes?
  database_version >= 110_000 # >= 11.0
end

#supports_pgcrypto_uuid?Boolean

Returns:

  • (Boolean)

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

def supports_pgcrypto_uuid?
  database_version >= 90400 # >= 9.4
end

#supports_savepoints?Boolean

Returns:

  • (Boolean)

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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 233

def supports_savepoints?
  true
end

#supports_transaction_isolation?Boolean

Returns:

  • (Boolean)

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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 197

def supports_transaction_isolation?
  true
end

#supports_validate_constraints?Boolean

Returns:

  • (Boolean)

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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 209

def supports_validate_constraints?
  true
end

#supports_views?Boolean

Returns:

  • (Boolean)

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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 217

def supports_views?
  true
end

#supports_virtual_columns?Boolean

Returns:

  • (Boolean)

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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 248

def supports_virtual_columns?
  database_version >= 120_000 # >= 12.0
end

#use_insert_returning?Boolean

Returns:

  • (Boolean)

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# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 500

def use_insert_returning?
  @use_insert_returning
end