| 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 182
182: def bound_variable_arg(arg, conn)
183: case arg
184: when Sequel::SQL::Blob
185: conn.escape_bytea(arg)
186: when Sequel::SQLTime
187: literal(arg)
188: when DateTime, Time
189: literal(arg)
190: else
191: arg
192: end
193: 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, and :sslmode sets whether postgres‘s sslmode. :connect_timeout and :ssl_mode are only supported if the pg driver is used.
# File lib/sequel/adapters/postgres.rb, line 201
201: def connect(server)
202: opts = server_opts(server)
203: conn = if SEQUEL_POSTGRES_USES_PG
204: connection_params = {
205: :host => opts[:host],
206: :port => opts[:port] || 5432,
207: :dbname => opts[:database],
208: :user => opts[:user],
209: :password => opts[:password],
210: :connect_timeout => opts[:connect_timeout] || 20,
211: :sslmode => opts[:sslmode]
212: }.delete_if { |key, value| blank_object?(value) }
213: Adapter.connect(connection_params)
214: else
215: Adapter.connect(
216: (opts[:host] unless blank_object?(opts[:host])),
217: opts[:port] || 5432,
218: nil, '',
219: opts[:database],
220: opts[:user],
221: opts[:password]
222: )
223: end
224: if encoding = opts[:encoding] || opts[:charset]
225: if conn.respond_to?(:set_client_encoding)
226: conn.set_client_encoding(encoding)
227: else
228: conn.async_exec("set client_encoding to '#{encoding}'")
229: end
230: end
231: conn.instance_variable_set(:@db, self)
232: conn.instance_variable_set(:@prepared_statements, {}) if SEQUEL_POSTGRES_USES_PG
233: connection_configuration_sqls.each{|sql| conn.execute(sql)}
234: conn
235: 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 239
239: def convert_infinite_timestamps=(v)
240: @convert_infinite_timestamps = case v
241: when Symbol
242: v
243: when 'nil'
244: :nil
245: when 'string'
246: :string
247: when 'float'
248: :float
249: when String
250: typecast_value_boolean(v)
251: else
252: false
253: end
254:
255: pr = old_pr = @use_iso_date_format ? TYPE_TRANSLATOR.method(:date) : Sequel.method(:string_to_date)
256: if v
257: pr = lambda do |val|
258: case val
259: when *INFINITE_TIMESTAMP_STRINGS
260: infinite_timestamp_value(val)
261: else
262: old_pr.call(val)
263: end
264: end
265: end
266: conversion_procs[1082] = pr
267: 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 347
347: def copy_into(table, opts={})
348: data = opts[:data]
349: data = Array(data) if data.is_a?(String)
350:
351: if block_given? && data
352: raise Error, "Cannot provide both a :data option and a block to copy_into"
353: elsif !block_given? && !data
354: raise Error, "Must provide either a :data option or a block to copy_into"
355: end
356:
357: synchronize(opts[:server]) do |conn|
358: conn.execute(copy_into_sql(table, opts))
359: begin
360: if block_given?
361: while buf = yield
362: conn.put_copy_data(buf)
363: end
364: else
365: data.each{|buff| conn.put_copy_data(buff)}
366: end
367: rescue Exception => e
368: conn.put_copy_end("ruby exception occurred while copying data into PostgreSQL")
369: ensure
370: conn.put_copy_end unless e
371: while res = conn.get_result
372: raise e if e
373: check_database_errors{res.check}
374: end
375: end
376: end
377: 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 307
307: def copy_table(table, opts={})
308: synchronize(opts[:server]) do |conn|
309: conn.execute(copy_table_sql(table, opts))
310: begin
311: if block_given?
312: while buf = conn.get_copy_data
313: yield buf
314: end
315: nil
316: else
317: b = ''
318: b << buf while buf = conn.get_copy_data
319: b
320: end
321: ensure
322: raise DatabaseDisconnectError, "disconnecting as a partial COPY may leave the connection in an unusable state" if buf
323: end
324: end
325: end
Disconnect given connection
# File lib/sequel/adapters/postgres.rb, line 270
270: def disconnect_connection(conn)
271: begin
272: conn.finish
273: rescue PGError
274: end
275: 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 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 400
400: def listen(channels, opts={}, &block)
401: check_database_errors do
402: synchronize(opts[:server]) do |conn|
403: begin
404: channels = Array(channels)
405: channels.each do |channel|
406: sql = "LISTEN "
407: dataset.send(:identifier_append, sql, channel)
408: conn.execute(sql)
409: end
410: opts[:after_listen].call(conn) if opts[:after_listen]
411: timeout = opts[:timeout] ? [opts[:timeout]] : []
412: if l = opts[:loop]
413: raise Error, 'calling #listen with :loop requires a block' unless block
414: loop_call = l.respond_to?(:call)
415: catch(:stop) do
416: loop do
417: conn.wait_for_notify(*timeout, &block)
418: l.call(conn) if loop_call
419: end
420: end
421: nil
422: else
423: conn.wait_for_notify(*timeout, &block)
424: end
425: ensure
426: conn.execute("UNLISTEN *")
427: end
428: end
429: end
430: 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 435
435: def to_application_timestamp(value)
436: if convert_infinite_timestamps
437: case value
438: when *INFINITE_TIMESTAMP_STRINGS
439: infinite_timestamp_value(value)
440: else
441: super
442: end
443: else
444: super
445: end
446: end