# File activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb, line 103
class_attribute :create_unlogged_tables, default: false

# File activerecord/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

# File activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb, line 121
class_attribute :datetime_type, default: :timestamp

# File activerecord/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

# File activerecord/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

# File activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb, line 307
def active?
  @lock.synchronize do
    @connection.query ";"
  end
  true
rescue PG::Error
  false
end

# File activerecord/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

# File activerecord/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

# File activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb, line 347
def disconnect!
  @lock.synchronize do
    super
    @connection.close rescue nil
  end
end

# File activerecord/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

# File activerecord/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

# File activerecord/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

# File activerecord/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

# File activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb, line 453
def extensions
  exec_query("SELECT extname FROM pg_extension", "SCHEMA").cast_values
end

# File activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb, line 252
def index_algorithms
  { concurrently: "CONCURRENTLY" }
end

# File activerecord/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

# File activerecord/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

# File activerecord/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

# File activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb, line 495
def session_auth=(user)
  clear_cache!
  execute("SET SESSION AUTHORIZATION #{user}")
end

# File activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb, line 372
def set_standard_conforming_strings
  execute("SET standard_conforming_strings = on", "SCHEMA")
end

# File activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb, line 380
def supports_advisory_locks?
  true
end

# File activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb, line 177
def supports_bulk_alter?
  true
end

# File activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb, line 205
def supports_check_constraints?
  true
end

# File activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb, line 229
def supports_comments?
  true
end

# File activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb, line 411
def supports_common_table_expressions?
  true
end

# File activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb, line 221
def supports_datetime_with_precision?
  true
end

# File activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb, line 376
def supports_ddl_transactions?
  true
end

# File activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb, line 213
def supports_deferrable_constraints?
  true
end

# File activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb, line 384
def supports_explain?
  true
end

# File activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb, line 193
def supports_expression_index?
  true
end

# File activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb, line 388
def supports_extensions?
  true
end

# File activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb, line 201
def supports_foreign_keys?
  true
end

# File activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb, line 396
def supports_foreign_tables?
  true
end

# File activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb, line 181
def supports_index_sort_order?
  true
end

# File activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb, line 241
def supports_insert_on_conflict?
  database_version >= 90500 # >= 9.5
end

# File activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb, line 237
def supports_insert_returning?
  true
end

# File activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb, line 225
def supports_json?
  true
end

# File activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb, line 415
def supports_lazy_transactions?
  true
end

# File activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb, line 392
def supports_materialized_views?
  true
end

# File activerecord/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

# File activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb, line 189
def supports_partial_index?
  true
end

# File activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb, line 185
def supports_partitioned_indexes?
  database_version >= 110_000 # >= 11.0
end

# File activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb, line 400
def supports_pgcrypto_uuid?
  database_version >= 90400 # >= 9.4
end

# File activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb, line 233
def supports_savepoints?
  true
end

# File activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb, line 197
def supports_transaction_isolation?
  true
end

# File activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb, line 209
def supports_validate_constraints?
  true
end

# File activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb, line 217
def supports_views?
  true
end

# File activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb, line 248
def supports_virtual_columns?
  database_version >= 120_000 # >= 12.0
end

# File activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb, line 500
def use_insert_returning?
  @use_insert_returning
end