Class | Sequel::Postgres::Database |
In: |
lib/sequel/adapters/postgres.rb
|
Parent: | Sequel::Database |
INFINITE_TIMESTAMP_STRINGS | = | ['infinity'.freeze, '-infinity'.freeze].freeze |
INFINITE_DATETIME_VALUES | = | ([PLUS_INFINITY, MINUS_INFINITY] + INFINITE_TIMESTAMP_STRINGS).freeze |
convert_infinite_timestamps | [R] | Whether infinite timestamps/dates should be converted on retrieval. By default, no conversion is done, so an error is raised if you attempt to retrieve an infinite timestamp/date. You can set this to :nil to convert to nil, :string to leave as a string, or :float to convert to an infinite float. |
Convert given argument so that it can be used directly by pg. Currently, pg doesn‘t handle fractional seconds in Time/DateTime or blobs with "\0", and it won‘t ever handle Sequel::SQLTime values correctly. Only public for use by the adapter, shouldn‘t be used by external code.
# File lib/sequel/adapters/postgres.rb, line 212 212: def bound_variable_arg(arg, conn) 213: case arg 214: when Sequel::SQL::Blob 215: {:value=>arg, :type=>17, :format=>1} 216: when Sequel::SQLTime 217: literal(arg) 218: when DateTime, Time 219: literal(arg) 220: else 221: arg 222: end 223: end
Connects to the database. In addition to the standard database options, using the :encoding or :charset option changes the client encoding for the connection, :connect_timeout is a connection timeout in seconds, :sslmode sets whether postgres‘s sslmode, and :notice_receiver handles server notices in a proc. :connect_timeout, :driver_options, :sslmode, and :notice_receiver are only supported if the pg driver is used.
# File lib/sequel/adapters/postgres.rb, line 232 232: def connect(server) 233: opts = server_opts(server) 234: if SEQUEL_POSTGRES_USES_PG 235: connection_params = { 236: :host => opts[:host], 237: :port => opts[:port] || 5432, 238: :dbname => opts[:database], 239: :user => opts[:user], 240: :password => opts[:password], 241: :connect_timeout => opts[:connect_timeout] || 20, 242: :sslmode => opts[:sslmode] 243: }.delete_if { |key, value| blank_object?(value) } 244: connection_params.merge!(opts[:driver_options]) if opts[:driver_options] 245: conn = Adapter.connect(connection_params) 246: 247: conn.instance_variable_set(:@prepared_statements, {}) 248: 249: if receiver = opts[:notice_receiver] 250: conn.set_notice_receiver(&receiver) 251: end 252: else 253: conn = Adapter.connect( 254: (opts[:host] unless blank_object?(opts[:host])), 255: opts[:port] || 5432, 256: nil, '', 257: opts[:database], 258: opts[:user], 259: opts[:password] 260: ) 261: end 262: 263: conn.instance_variable_set(:@db, self) 264: 265: if encoding = opts[:encoding] || opts[:charset] 266: if conn.respond_to?(:set_client_encoding) 267: conn.set_client_encoding(encoding) 268: else 269: conn.async_exec("set client_encoding to '#{encoding}'") 270: end 271: end 272: 273: connection_configuration_sqls.each{|sql| conn.execute(sql)} 274: conn 275: end
Set whether to allow infinite timestamps/dates. Make sure the conversion proc for date reflects that setting.
# File lib/sequel/adapters/postgres.rb, line 279 279: def convert_infinite_timestamps=(v) 280: @convert_infinite_timestamps = case v 281: when Symbol 282: v 283: when 'nil' 284: :nil 285: when 'string' 286: :string 287: when 'float' 288: :float 289: when String 290: typecast_value_boolean(v) 291: else 292: false 293: end 294: 295: pr = old_pr = @use_iso_date_format ? TYPE_TRANSLATOR.method(:date) : Sequel.method(:string_to_date) 296: if v 297: pr = lambda do |val| 298: case val 299: when *INFINITE_TIMESTAMP_STRINGS 300: infinite_timestamp_value(val) 301: else 302: old_pr.call(val) 303: end 304: end 305: end 306: conversion_procs[1082] = pr 307: end
copy_into uses PostgreSQL‘s +COPY FROM STDIN+ SQL statement to do very fast inserts into a table using input preformatting in either CSV or PostgreSQL text format. This method is only supported if pg 0.14.0+ is the underlying ruby driver. This method should only be called if you want results returned to the client. If you are using +COPY FROM+ with a filename, you should just use run instead of this method.
The following options are respected:
:columns : | The columns to insert into, with the same order as the columns in the input data. If this isn‘t given, uses all columns in the table. |
:data : | The data to copy to PostgreSQL, which should already be in CSV or PostgreSQL text format. This can be either a string, or any object that responds to each and yields string. |
:format : | The format to use. text is the default, so this should be :csv or :binary. |
:options : | An options SQL string to use, which should contain comma separated options. |
:server : | The server on which to run the query. |
If a block is provided and :data option is not, this will yield to the block repeatedly. The block should return a string, or nil to signal that it is finished.
# File lib/sequel/adapters/postgres.rb, line 411 411: def copy_into(table, opts=OPTS) 412: data = opts[:data] 413: data = Array(data) if data.is_a?(String) 414: 415: if block_given? && data 416: raise Error, "Cannot provide both a :data option and a block to copy_into" 417: elsif !block_given? && !data 418: raise Error, "Must provide either a :data option or a block to copy_into" 419: end 420: 421: synchronize(opts[:server]) do |conn| 422: conn.execute(copy_into_sql(table, opts)) 423: begin 424: if block_given? 425: while buf = yield 426: conn.put_copy_data(buf) 427: end 428: else 429: data.each{|buff| conn.put_copy_data(buff)} 430: end 431: rescue Exception => e 432: conn.put_copy_end("ruby exception occurred while copying data into PostgreSQL") 433: ensure 434: conn.put_copy_end unless e 435: while res = conn.get_result 436: raise e if e 437: check_database_errors{res.check} 438: end 439: end 440: end 441: end
copy_table uses PostgreSQL‘s +COPY TO STDOUT+ SQL statement to return formatted results directly to the caller. This method is only supported if pg is the underlying ruby driver. This method should only be called if you want results returned to the client. If you are using +COPY TO+ with a filename, you should just use run instead of this method.
The table argument supports the following types:
String : | Uses the first argument directly as literal SQL. If you are using a version of PostgreSQL before 9.0, you will probably want to use a string if you are using any options at all, as the syntax Sequel uses for options is only compatible with PostgreSQL 9.0+. |
Dataset : | Uses a query instead of a table name when copying. |
other : | Uses a table name (usually a symbol) when copying. |
The following options are respected:
:format : | The format to use. text is the default, so this should be :csv or :binary. |
:options : | An options SQL string to use, which should contain comma separated options. |
:server : | The server on which to run the query. |
If a block is provided, the method continually yields to the block, one yield per row. If a block is not provided, a single string is returned with all of the data.
# File lib/sequel/adapters/postgres.rb, line 371 371: def copy_table(table, opts=OPTS) 372: synchronize(opts[:server]) do |conn| 373: conn.execute(copy_table_sql(table, opts)) 374: begin 375: if block_given? 376: while buf = conn.get_copy_data 377: yield buf 378: end 379: nil 380: else 381: b = String.new 382: b << buf while buf = conn.get_copy_data 383: b 384: end 385: ensure 386: raise DatabaseDisconnectError, "disconnecting as a partial COPY may leave the connection in an unusable state" if buf 387: end 388: end 389: end
Disconnect given connection
# File lib/sequel/adapters/postgres.rb, line 310 310: def disconnect_connection(conn) 311: conn.finish 312: rescue PGError, IOError 313: nil 314: end
Return a hash of information about the related PGError (or Sequel::DatabaseError that wraps a PGError), with the following entries:
:schema : | The schema name related to the error |
:table : | The table name related to the error |
:column : | the column name related to the error |
:constraint : | The constraint name related to the error |
:type : | The datatype name related to the error |
This requires a PostgreSQL 9.3+ server and 9.3+ client library, and ruby-pg 0.16.0+ to be supported.
# File lib/sequel/adapters/postgres.rb, line 328 328: def error_info(e) 329: e = e.wrapped_exception if e.is_a?(DatabaseError) 330: r = e.result 331: h = {} 332: h[:schema] = r.error_field(::PG::PG_DIAG_SCHEMA_NAME) 333: h[:table] = r.error_field(::PG::PG_DIAG_TABLE_NAME) 334: h[:column] = r.error_field(::PG::PG_DIAG_COLUMN_NAME) 335: h[:constraint] = r.error_field(::PG::PG_DIAG_CONSTRAINT_NAME) 336: h[:type] = r.error_field(::PG::PG_DIAG_DATATYPE_NAME) 337: h 338: end
Listens on the given channel (or multiple channels if channel is an array), waiting for notifications. After a notification is received, or the timeout has passed, stops listening to the channel. Options:
:after_listen : | An object that responds to call that is called with the underlying connection after the LISTEN statement is sent, but before the connection starts waiting for notifications. |
:loop : | Whether to continually wait for notifications, instead of just waiting for a single notification. If this option is given, a block must be provided. If this object responds to call, it is called with the underlying connection after each notification is received (after the block is called). If a :timeout option is used, and a callable object is given, the object will also be called if the timeout expires. If :loop is used and you want to stop listening, you can either break from inside the block given to listen, or you can throw :stop from inside the :loop object‘s call method or the block. |
:server : | The server on which to listen, if the sharding support is being used. |
:timeout : | How long to wait for a notification, in seconds (can provide a float value for fractional seconds). If this object responds to call, it will be called and should return the number of seconds to wait. If the loop option is also specified, the object will be called on each iteration to obtain a new timeout value. If not given or nil, waits indefinitely. |
This method is only supported if pg is used as the underlying ruby driver. It returns the channel the notification was sent to (as a string), unless :loop was used, in which case it returns nil. If a block is given, it is yielded 3 arguments:
# File lib/sequel/adapters/postgres.rb, line 466 466: def listen(channels, opts=OPTS, &block) 467: check_database_errors do 468: synchronize(opts[:server]) do |conn| 469: begin 470: channels = Array(channels) 471: channels.each do |channel| 472: sql = "LISTEN ".dup 473: dataset.send(:identifier_append, sql, channel) 474: conn.execute(sql) 475: end 476: opts[:after_listen].call(conn) if opts[:after_listen] 477: timeout = opts[:timeout] 478: if timeout 479: timeout_block = timeout.respond_to?(:call) ? timeout : proc{timeout} 480: end 481: 482: if l = opts[:loop] 483: raise Error, 'calling #listen with :loop requires a block' unless block 484: loop_call = l.respond_to?(:call) 485: catch(:stop) do 486: loop do 487: t = timeout_block ? [timeout_block.call] : [] 488: conn.wait_for_notify(*t, &block) 489: l.call(conn) if loop_call 490: end 491: end 492: nil 493: else 494: t = timeout_block ? [timeout_block.call] : [] 495: conn.wait_for_notify(*t, &block) 496: end 497: ensure 498: conn.execute("UNLISTEN *") 499: end 500: end 501: end 502: end
If convert_infinite_timestamps is true and the value is infinite, return an appropriate value based on the convert_infinite_timestamps setting.
# File lib/sequel/adapters/postgres.rb, line 507 507: def to_application_timestamp(value) 508: if convert_infinite_timestamps 509: case value 510: when *INFINITE_TIMESTAMP_STRINGS 511: infinite_timestamp_value(value) 512: else 513: super 514: end 515: else 516: super 517: end 518: end