Class: ActiveRecord::ConnectionAdapters::PostgreSQLAdapter

Inherits:
AbstractAdapter
  • Object
show all
Includes:
ActiveRecord::ConnectionAdapters::PostgreSQL::DatabaseStatements, ActiveRecord::ConnectionAdapters::PostgreSQL::Quoting, ActiveRecord::ConnectionAdapters::PostgreSQL::ReferentialIntegrity, ActiveRecord::ConnectionAdapters::PostgreSQL::SchemaStatements
Defined in:
lib/active_record/connection_adapters/postgresql_adapter.rb

Overview

Active Record PostgreSQL Adapter

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

ActiveRecord::ConnectionAdapters::PostgreSQL::Quoting::QUOTED_COLUMN_NAMES, ActiveRecord::ConnectionAdapters::PostgreSQL::Quoting::QUOTED_TABLE_NAMES

Constants inherited from AbstractAdapter

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

Constants included from QueryCache

QueryCache::DEFAULT_SIZE

Instance Attribute Summary

Attributes inherited from AbstractAdapter

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

Attributes included from QueryCache

#query_cache

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, #build_explain_clause, #commit_db_transaction, #exec_insert, #exec_restart_db_transaction, #exec_rollback_db_transaction, #execute, #explain, #high_precision_current_timestamp, #query, #set_constraints, #write_query?

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

#add_column, #add_exclusion_constraint, #add_foreign_key, #add_index, #add_index_options, #add_unique_constraint, #build_change_column_default_definition, #build_change_column_definition, #build_create_index_definition, #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, #exclusion_constraint_options, #exclusion_constraints, #foreign_key_column_for, #foreign_keys, #foreign_table_exists?, #foreign_tables, #index_name, #index_name_exists?, #indexes, #inherited_table_names, #pk_and_sequence_for, #primary_keys, #quoted_include_columns_for_index, #recreate_database, #remove_exclusion_constraint, #remove_index, #remove_unique_constraint, #rename_column, #rename_index, #rename_table, #reset_pk_sequence!, #schema_creation, #schema_exists?, #schema_names, #schema_search_path, #schema_search_path=, #serial_sequence, #set_pk_sequence!, #table_comment, #table_options, #table_partition_definition, #type_to_sql, #unique_constraint_options, #unique_constraints, #update_table_definition, #validate_check_constraint, #validate_constraint, #validate_foreign_key

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

#check_all_foreign_keys_valid!, #disable_referential_integrity

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

#check_int_in_range, #escape_bytea, #lookup_cast_type_from_column, #quote, #quote_default_expression, #quote_schema_name, #quote_string, #quote_table_name_for_assignment, #quoted_binary, #quoted_date, #type_cast, #unescape_bytea

Methods inherited from AbstractAdapter

#adapter_name, #advisory_locks_enabled?, #async_enabled?, build_read_query_regexp, #case_insensitive_comparison, #case_sensitive_comparison, #check_all_foreign_keys_valid!, #check_if_write_query, #clean!, #clear_cache!, #close, #connect!, #connection_class, #connection_retries, #create_virtual_table, database_exists?, #database_exists?, #database_version, #default_timezone, #default_uniqueness_comparison, #disable_referential_integrity, #drop_virtual_table, #expire, extended_type_map, find_cmd_and_exec, #inspect, #lease, #lock_thread=, #prefetch_primary_key?, #prepared_statements?, #prepared_statements_disabled_cache, #preventing_writes?, #raw_connection, #reconnect!, register_class_with_precision, #replica?, #requires_reloading?, #retry_deadline, #return_value_after_insert?, #role, #savepoint_errors_invalidate_transactions?, #schema_cache, #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, #valid_type?, validate_default_timezone, #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, #query_cache_enabled, #select_all, #uncached

Methods included from DatabaseLimits

#index_name_length, #table_alias_length, #table_name_length

Methods included from Quoting

#cast_bound_value, #lookup_cast_type_from_column, #quote, #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_deferred_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_restart_db_transaction, #exec_rollback_db_transaction, #exec_update, #execute, #explain, #high_precision_current_timestamp, #insert, #insert_fixture, #insert_fixtures_set, #internal_exec_query, #mark_transaction_written_if_write, #query, #query_value, #query_values, #raw_exec_query, #reset_isolation_level, #reset_sequence!, #reset_transaction, #restart_db_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, #build_add_column_definition, #build_change_column_default_definition, #build_create_index_definition, #build_create_join_table_definition, #build_create_table_definition, #bulk_change_table, #change_column, #change_column_comment, #change_column_default, #change_column_null, #change_table, #change_table_comment, #check_constraint_exists?, #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, #max_index_name_size, #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, #schema_creation, #table_alias_for, #table_comment, #table_exists?, #table_options, #tables, #type_to_sql, #update_table_definition, #use_foreign_keys?, #valid_column_definition_options, #valid_primary_key_options, #valid_table_definition_options, #view_exists?, #views

Constructor Details

#initialize ⇒ PostgreSQLAdapter

Initializes and connects a PostgreSQL adapter.



320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
 
# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 320

def initialize(...)
  super

  conn_params = @config.compact

  # Map ActiveRecords param names to PGs.
  conn_params[:user] = conn_params.delete(:username) if conn_params[:username]
  conn_params[:dbname] = conn_params.delete(:database) if conn_params[:database]

  # Forward only valid config params to PG::Connection.connect.
  valid_conn_param_keys = PG::Connection.conndefaults_hash.keys + [:requiressl]
  conn_params.slice!(*valid_conn_param_keys)

  @connection_parameters = conn_params

  @max_identifier_length = nil
  @type_map = nil
  @raw_connection = nil
  @notice_receiver_sql_warnings = []

  @use_insert_returning = @config.key?(:insert_returning) ? self.class.type_cast_config_to_boolean(@config[:insert_returning]) : true
end

Class Method Details

.dbconsole(config, options = {}) ⇒ Object 



73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
 
# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 73

def dbconsole(config, options = {})
  pg_config = config.configuration_hash

  ENV["PGUSER"]         = pg_config[:username] if pg_config[:username]
  ENV["PGHOST"]         = pg_config[:host] if pg_config[:host]
  ENV["PGPORT"]         = pg_config[:port].to_s if pg_config[:port]
  ENV["PGPASSWORD"]     = pg_config[:password].to_s if pg_config[:password] && options[:include_password]
  ENV["PGSSLMODE"]      = pg_config[:sslmode].to_s if pg_config[:sslmode]
  ENV["PGSSLCERT"]      = pg_config[:sslcert].to_s if pg_config[:sslcert]
  ENV["PGSSLKEY"]       = pg_config[:sslkey].to_s if pg_config[:sslkey]
  ENV["PGSSLROOTCERT"]  = pg_config[:sslrootcert].to_s if pg_config[:sslrootcert]
  if pg_config[:variables]
    ENV["PGOPTIONS"] = pg_config[:variables].filter_map do |name, value|
      "-c #{name}=#{value.to_s.gsub(/[ \\]/, '\\\\\0')}" unless value == ":default" || value == :default
    end.join(" ")
  end
  find_cmd_and_exec(ActiveRecord.database_cli[:postgresql], config.database)
end

.initialize_type_map(m) ⇒ Object

:nodoc:



669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
 
# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 669

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)

  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_types ⇒ Object

:nodoc:



403
404
405
406
407
408
409
 
# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 403

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 



57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
 
# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 57

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

Instance Method Details

#active? ⇒ Boolean

Is this connection alive and ready for queries?

Returns:

  • (Boolean) 


348
349
350
351
352
353
354
355
356
 
# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 348

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

#add_enum_value(type_name, value, **options) ⇒ Object

Add enum value to an existing enum type.



585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
 
# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 585

def add_enum_value(type_name, value, **options)
  before, after = options.values_at(:before, :after)
  sql = +"ALTER TYPE #{quote_table_name(type_name)} ADD VALUE"
  sql << " IF NOT EXISTS" if options[:if_not_exists]
  sql << " '#{value}'"

  if before && after
    raise ArgumentError, "Cannot have both :before and :after at the same time"
  elsif before
    sql << " BEFORE '#{before}'"
  elsif after
    sql << " AFTER '#{after}'"
  end

  execute(sql).tap { reload_type_map }
end

#build_insert_sql(insert) ⇒ Object

:nodoc:



643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
 
# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 643

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_version ⇒ Object

:nodoc:



662
663
664
665
666
 
# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 662

def check_version # :nodoc:
  if database_version < 9_03_00 # < 9.3
    raise "Your version of PostgreSQL (#{database_version}) is too old. Active Record supports PostgreSQL >= 9.3."
  end
end

#connected? ⇒ Boolean

Returns:

  • (Boolean) 


343
344
345
 
# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 343

def connected?
  !(@raw_connection.nil? || @raw_connection.finished?)
end

#create_enum(name, values, **options) ⇒ Object

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



540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
 
# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 540

def create_enum(name, values, **options)
  sql_values = values.map { |s| quote(s) }.join(", ")
  scope = quoted_scope(name)
  query = <<~SQL
    DO $$
    BEGIN
        IF NOT EXISTS (
          SELECT 1
          FROM pg_type t
          JOIN pg_namespace n ON t.typnamespace = n.oid
          WHERE t.typname = #{scope[:name]}
            AND n.nspname = #{scope[:schema]}
        ) THEN
            CREATE TYPE #{quote_table_name(name)} AS ENUM (#{sql_values});
        END IF;
    END
    $$;
  SQL
  internal_exec_query(query).tap { reload_type_map }
end

#create_unlogged_tables ⇒ Object

: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 to your test.rb file:

ActiveSupport.on_load(:active_record_postgresqladapter) do
  self.create_unlogged_tables = true
end



105
 
# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 105

class_attribute :create_unlogged_tables, default: false

#datetime_type ⇒ Object

: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.



123
 
# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 123

class_attribute :datetime_type, default: :timestamp

#decode_dates ⇒ Object

:singleton-method: Toggles automatic decoding of date columns.

ActiveRecord::ConnectionAdapters::PostgreSQLAdapter.select_value("select '2024-01-01'::date").class #=> String
ActiveRecord::ConnectionAdapters::PostgreSQLAdapter.decode_dates = true
ActiveRecord::ConnectionAdapters::PostgreSQLAdapter.select_value("select '2024-01-01'::date").class #=> Date



132
 
# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 132

class_attribute :decode_dates, default: false

#default_index_type?(index) ⇒ Boolean

:nodoc:

Returns:

  • (Boolean) 


639
640
641
 
# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 639

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

#disable_extension(name, force: false) ⇒ Object

Removes an extension from the database.

:force

Set to :cascade to drop dependent objects as well. Defaults to false.



485
486
487
488
489
490
 
# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 485

def disable_extension(name, force: false)
  _schema, name = name.to_s.split(".").values_at(-2, -1)
  internal_exec_query("DROP EXTENSION IF EXISTS \"#{name}\"#{' CASCADE' if force == :cascade}").tap {
    reload_type_map
  }
end

#discard! ⇒ Object

:nodoc:



393
394
395
396
397
 
# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 393

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

#disconnect! ⇒ Object

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



385
386
387
388
389
390
391
 
# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 385

def disconnect!
  @lock.synchronize do
    super
    @raw_connection&.close rescue nil
    @raw_connection = nil
  end
end

#drop_enum(name, values = nil, **options) ⇒ Object

Drops an enum type.

If the if_exists: true option is provided, the enum is dropped only if it exists. Otherwise, if the enum doesn’t exist, an error is raised.

The values parameter will be ignored if present. It can be helpful to provide this in a migration’s change method so it can be reverted. In that case, values will be used by #create_enum.



570
571
572
573
574
575
 
# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 570

def drop_enum(name, values = nil, **options)
  query = <<~SQL
    DROP TYPE#{' IF EXISTS' if options[:if_exists]} #{quote_table_name(name)};
  SQL
  internal_exec_query(query).tap { reload_type_map }
end

#enable_extension(name) ⇒ Object 



472
473
474
475
476
477
478
 
# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 472

def enable_extension(name, **)
  schema, name = name.to_s.split(".").values_at(-2, -1)
  sql = +"CREATE EXTENSION IF NOT EXISTS \"#{name}\""
  sql << " SCHEMA #{schema}" if schema

  internal_exec_query(sql).tap { reload_type_map }
end

#enum_types ⇒ Object

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



517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
 
# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 517

def enum_types
  query = <<~SQL
    SELECT
      type.typname AS name,
      type.OID AS oid,
      n.nspname AS schema,
      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)
    JOIN pg_namespace n ON type.typnamespace = n.oid
    WHERE n.nspname = ANY (current_schemas(false))
    GROUP BY type.OID, n.nspname, type.typname;
  SQL

  internal_exec_query(query, "SCHEMA", allow_retry: true, materialize_transactions: false).cast_values.each_with_object({}) do |row, memo|
    name, schema = row[0], row[2]
    schema = nil if schema == current_schema
    full_name = [schema, name].compact.join(".")
    memo[full_name] = row.last
  end.to_a
end

#extension_available?(name) ⇒ Boolean

Returns:

  • (Boolean) 


492
493
494
 
# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 492

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

#extension_enabled?(name) ⇒ Boolean

Returns:

  • (Boolean) 


496
497
498
 
# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 496

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

#extensions ⇒ Object 



500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
 
# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 500

def extensions
  query = <<~SQL
    SELECT
      pg_extension.extname,
      n.nspname AS schema
    FROM pg_extension
    JOIN pg_namespace n ON pg_extension.extnamespace = n.oid
  SQL

  internal_exec_query(query, "SCHEMA", allow_retry: true, materialize_transactions: false).cast_values.map do |row|
    name, schema = row[0], row[1]
    schema = nil if schema == current_schema
    [schema, name].compact.join(".")
  end
end

#get_advisory_lock(lock_id) ⇒ Object

:nodoc:



458
459
460
461
462
463
 
# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 458

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_version ⇒ Object

Returns the version of the connected PostgreSQL server.



632
633
634
635
636
 
# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 632

def get_database_version # :nodoc:
  with_raw_connection do |conn|
    conn.server_version
  end
end

#index_algorithms ⇒ Object 



291
292
293
 
# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 291

def index_algorithms
  { concurrently: "CONCURRENTLY" }
end

#max_identifier_length ⇒ Object

Returns the configured supported identifier length supported by PostgreSQL



617
618
619
 
# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 617

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

#native_database_types ⇒ Object

:nodoc:



399
400
401
 
# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 399

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

#release_advisory_lock(lock_id) ⇒ Object

:nodoc:



465
466
467
468
469
470
 
# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 465

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_map ⇒ Object

:nodoc:



358
359
360
361
362
363
364
365
366
367
368
 
# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 358

def reload_type_map # :nodoc:
  @lock.synchronize do
    if @type_map
      type_map.clear
    else
      @type_map = Type::HashLookupTypeMap.new
    end

    initialize_type_map
  end
end

#rename_enum(name, **options) ⇒ Object

Rename an existing enum type to something else.



578
579
580
581
582
 
# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 578

def rename_enum(name, **options)
  to = options.fetch(:to) { raise ArgumentError, ":to is required" }

  exec_query("ALTER TYPE #{quote_table_name(name)} RENAME TO #{to}").tap { reload_type_map }
end

#rename_enum_value(type_name, **options) ⇒ Object

Rename enum value on an existing enum type.



603
604
605
606
607
608
609
610
611
612
613
614
 
# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 603

def rename_enum_value(type_name, **options)
  unless database_version >= 10_00_00 # >= 10.0
    raise ArgumentError, "Renaming enum values is only supported in PostgreSQL 10 or later"
  end

  from = options.fetch(:from) { raise ArgumentError, ":from is required" }
  to = options.fetch(:to) { raise ArgumentError, ":to is required" }

  execute("ALTER TYPE #{quote_table_name(type_name)} RENAME VALUE '#{from}' TO '#{to}'").tap {
    reload_type_map
  }
end

#reset! ⇒ Object 



370
371
372
373
374
375
376
377
378
379
380
381
 
# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 370

def reset!
  @lock.synchronize do
    return connect! unless @raw_connection

    unless @raw_connection.transaction_status == ::PG::PQTRANS_IDLE
      @raw_connection.query "ROLLBACK"
    end
    @raw_connection.query "DISCARD ALL"

    super
  end
end

#session_auth=(user) ⇒ Object

Set the authorized user for this session



622
623
624
625
 
# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 622

def session_auth=(user)
  clear_cache!
  internal_execute("SET SESSION AUTHORIZATION #{user}", nil, materialize_transactions: true)
end

#set_standard_conforming_strings ⇒ Object 



411
412
413
 
# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 411

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

#supports_advisory_locks? ⇒ Boolean

Returns:

  • (Boolean) 


419
420
421
 
# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 419

def supports_advisory_locks?
  true
end

#supports_bulk_alter? ⇒ Boolean

Returns:

  • (Boolean) 


188
189
190
 
# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 188

def supports_bulk_alter?
  true
end

#supports_check_constraints? ⇒ Boolean

Returns:

  • (Boolean) 


220
221
222
 
# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 220

def supports_check_constraints?
  true
end

#supports_comments? ⇒ Boolean

Returns:

  • (Boolean) 


252
253
254
 
# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 252

def supports_comments?
  true
end

#supports_common_table_expressions? ⇒ Boolean

Returns:

  • (Boolean) 


450
451
452
 
# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 450

def supports_common_table_expressions?
  true
end

#supports_datetime_with_precision? ⇒ Boolean

Returns:

  • (Boolean) 


244
245
246
 
# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 244

def supports_datetime_with_precision?
  true
end

#supports_ddl_transactions? ⇒ Boolean

Returns:

  • (Boolean) 


415
416
417
 
# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 415

def supports_ddl_transactions?
  true
end

#supports_deferrable_constraints? ⇒ Boolean

Returns:

  • (Boolean) 


236
237
238
 
# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 236

def supports_deferrable_constraints?
  true
end

#supports_exclusion_constraints? ⇒ Boolean

Returns:

  • (Boolean) 


224
225
226
 
# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 224

def supports_exclusion_constraints?
  true
end

#supports_explain? ⇒ Boolean

Returns:

  • (Boolean) 


423
424
425
 
# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 423

def supports_explain?
  true
end

#supports_expression_index? ⇒ Boolean

Returns:

  • (Boolean) 


208
209
210
 
# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 208

def supports_expression_index?
  true
end

#supports_extensions? ⇒ Boolean

Returns:

  • (Boolean) 


427
428
429
 
# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 427

def supports_extensions?
  true
end

#supports_foreign_keys? ⇒ Boolean

Returns:

  • (Boolean) 


216
217
218
 
# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 216

def supports_foreign_keys?
  true
end

#supports_foreign_tables? ⇒ Boolean

Returns:

  • (Boolean) 


435
436
437
 
# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 435

def supports_foreign_tables?
  true
end

#supports_identity_columns? ⇒ Boolean

:nodoc:

Returns:

  • (Boolean) 


279
280
281
 
# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 279

def supports_identity_columns? # :nodoc:
  database_version >= 10_00_00 # >= 10.0
end

#supports_index_include? ⇒ Boolean

Returns:

  • (Boolean) 


204
205
206
 
# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 204

def supports_index_include?
  database_version >= 11_00_00 # >= 11.0
end

#supports_index_sort_order? ⇒ Boolean

Returns:

  • (Boolean) 


192
193
194
 
# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 192

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) 


268
269
270
 
# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 268

def supports_insert_on_conflict?
  database_version >= 9_05_00 # >= 9.5
end

#supports_insert_returning? ⇒ Boolean

Returns:

  • (Boolean) 


264
265
266
 
# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 264

def supports_insert_returning?
  true
end

#supports_json? ⇒ Boolean

Returns:

  • (Boolean) 


248
249
250
 
# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 248

def supports_json?
  true
end

#supports_lazy_transactions? ⇒ Boolean

Returns:

  • (Boolean) 


454
455
456
 
# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 454

def supports_lazy_transactions?
  true
end

#supports_materialized_views? ⇒ Boolean

Returns:

  • (Boolean) 


431
432
433
 
# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 431

def supports_materialized_views?
  true
end

#supports_native_partitioning? ⇒ Boolean

:nodoc:

Returns:

  • (Boolean) 


287
288
289
 
# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 287

def supports_native_partitioning? # :nodoc:
  database_version >= 10_00_00 # >= 10.0
end

#supports_nulls_not_distinct? ⇒ Boolean

Returns:

  • (Boolean) 


283
284
285
 
# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 283

def supports_nulls_not_distinct?
  database_version >= 15_00_00 # >= 15.0
end

#supports_optimizer_hints? ⇒ Boolean

Returns:

  • (Boolean) 


443
444
445
446
447
448
 
# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 443

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) 


200
201
202
 
# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 200

def supports_partial_index?
  true
end

#supports_partitioned_indexes? ⇒ Boolean

Returns:

  • (Boolean) 


196
197
198
 
# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 196

def supports_partitioned_indexes?
  database_version >= 11_00_00 # >= 11.0
end

#supports_pgcrypto_uuid? ⇒ Boolean

Returns:

  • (Boolean) 


439
440
441
 
# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 439

def supports_pgcrypto_uuid?
  database_version >= 9_04_00 # >= 9.4
end

#supports_restart_db_transaction? ⇒ Boolean

Returns:

  • (Boolean) 


260
261
262
 
# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 260

def supports_restart_db_transaction?
  database_version >= 12_00_00 # >= 12.0
end

#supports_savepoints? ⇒ Boolean

Returns:

  • (Boolean) 


256
257
258
 
# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 256

def supports_savepoints?
  true
end

#supports_transaction_isolation? ⇒ Boolean

Returns:

  • (Boolean) 


212
213
214
 
# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 212

def supports_transaction_isolation?
  true
end

#supports_unique_constraints? ⇒ Boolean

Returns:

  • (Boolean) 


228
229
230
 
# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 228

def supports_unique_constraints?
  true
end

#supports_validate_constraints? ⇒ Boolean

Returns:

  • (Boolean) 


232
233
234
 
# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 232

def supports_validate_constraints?
  true
end

#supports_views? ⇒ Boolean

Returns:

  • (Boolean) 


240
241
242
 
# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 240

def supports_views?
  true
end

#supports_virtual_columns? ⇒ Boolean

Returns:

  • (Boolean) 


275
276
277
 
# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 275

def supports_virtual_columns?
  database_version >= 12_00_00 # >= 12.0
end

#use_insert_returning? ⇒ Boolean

Returns:

  • (Boolean) 


627
628
629
 
# File 'lib/active_record/connection_adapters/postgresql_adapter.rb', line 627

def use_insert_returning?
  @use_insert_returning
end