Class ActiveRecord::ConnectionAdapters::PostgreSQLAdapter < ActiveRecord::ConnectionAdapters::AbstractAdapter

# File activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb, line 211
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(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

# File activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb, line 249
def active?
  @lock.synchronize do
    @connection.query "SELECT 1"
  end
  true
rescue PG::Error
  false
end

# File activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb, line 238
def clear_cache!
  @lock.synchronize do
    @statements.clear
  end
end

# File activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb, line 345
def disable_extension(name)
  exec_query("DROP EXTENSION IF EXISTS \"#{name}\" CASCADE").tap {
    reload_type_map
  }
end

# File activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb, line 281
def disconnect!
  @lock.synchronize do
    super
    @connection.close rescue nil
  end
end

# File activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb, line 339
def enable_extension(name)
  exec_query("CREATE EXTENSION IF NOT EXISTS \"#{name}\"").tap {
    reload_type_map
  }
end

# File activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb, line 351
def extension_enabled?(name)
  if supports_extensions?
    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
end

# File activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb, line 358
def extensions
  if supports_extensions?
    exec_query("SELECT extname FROM pg_extension", "SCHEMA").cast_values
  else
    super
  end
end

# File activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb, line 178
def index_algorithms
  { concurrently: "CONCURRENTLY" }
end

# File activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb, line 397
def postgresql_version
  @connection.server_version
end

# File activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb, line 259
def reconnect!
  @lock.synchronize do
    super
    @connection.reset
    configure_connection
  end
end

# File activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb, line 267
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

# File activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb, line 373
def session_auth=(user)
  clear_cache!
  execute("SET SESSION AUTHORIZATION #{user}")
end

# File activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb, line 292
def set_standard_conforming_strings
  execute("SET standard_conforming_strings = on", "SCHEMA")
end

# File activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb, line 300
def supports_advisory_locks?
  true
end

# File activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb, line 170
def supports_comments?
  true
end

# File activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb, line 162
def supports_datetime_with_precision?
  true
end

# File activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb, line 296
def supports_ddl_transactions?
  true
end

# File activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb, line 304
def supports_explain?
  true
end

# File activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb, line 146
def supports_expression_index?
  true
end

# File activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb, line 308
def supports_extensions?
  true
end

# File activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb, line 154
def supports_foreign_keys?
  true
end

# File activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb, line 138
def supports_index_sort_order?
  true
end

# File activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb, line 166
def supports_json?
  postgresql_version >= 90200
end

# File activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb, line 317
def supports_materialized_views?
  postgresql_version >= 90300
end

# File activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb, line 142
def supports_partial_index?
  true
end

# File activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb, line 321
def supports_pgcrypto_uuid?
  postgresql_version >= 90400
end

# File activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb, line 313
def supports_ranges?
  postgresql_version >= 90200
end

# File activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb, line 174
def supports_savepoints?
  true
end

# File activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb, line 134
def supports_statement_cache?
  true
end

# File activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb, line 150
def supports_transaction_isolation?
  true
end

# File activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb, line 158
def supports_views?
  true
end

# File activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb, line 367
def table_alias_length
  @max_identifier_length ||= query_value("SHOW max_identifier_length", "SCHEMA").to_i
end

# File activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb, line 244
def truncate(table_name, name = nil)
  exec_query "TRUNCATE TABLE #{quote_table_name(table_name)}", name, []
end

# File activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb, line 378
def use_insert_returning?
  @use_insert_returning
end