Class Sequel::Postgres::Database
In: lib/sequel/adapters/postgres.rb
Parent: Sequel::Database

Methods

Included Modules

Sequel::Postgres::DatabaseMethods

Constants

DATABASE_ERROR_CLASSES = [PGError].freeze

Public Instance methods

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". Only public for use by the adapter, shouldn‘t be used by external code.

[Source]

     # File lib/sequel/adapters/postgres.rb, line 159
159:       def bound_variable_arg(arg, conn)
160:         case arg
161:         when Sequel::SQL::Blob
162:           {:value=>arg, :type=>17, :format=>1}
163:         when DateTime, Time
164:           literal(arg)
165:         else
166:           arg
167:         end
168:       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.

[Source]

     # File lib/sequel/adapters/postgres.rb, line 177
177:       def connect(server)
178:         opts = server_opts(server)
179:         if USES_PG
180:           connection_params = {
181:             :host => opts[:host],
182:             :port => opts[:port] || 5432,
183:             :dbname => opts[:database],
184:             :user => opts[:user],
185:             :password => opts[:password],
186:             :connect_timeout => opts[:connect_timeout] || 20,
187:             :sslmode => opts[:sslmode],
188:             :sslrootcert => opts[:sslrootcert]
189:           }.delete_if { |key, value| blank_object?(value) }
190:           connection_params.merge!(opts[:driver_options]) if opts[:driver_options]
191:           conn = Adapter.connect(connection_params)
192: 
193:           conn.instance_variable_set(:@prepared_statements, {})
194: 
195:           if receiver = opts[:notice_receiver]
196:             conn.set_notice_receiver(&receiver)
197:           end
198:         else
199:           unless typecast_value_boolean(@opts.fetch(:force_standard_strings, true))
200:             raise Error, "Cannot create connection using postgres-pr unless force_standard_strings is set"
201:           end
202: 
203:           conn = Adapter.connect(
204:             (opts[:host] unless blank_object?(opts[:host])),
205:             opts[:port] || 5432,
206:             nil, '',
207:             opts[:database],
208:             opts[:user],
209:             opts[:password]
210:           )
211:         end
212: 
213:         conn.instance_variable_set(:@db, self)
214: 
215:         if encoding = opts[:encoding] || opts[:charset]
216:           if conn.respond_to?(:set_client_encoding)
217:             conn.set_client_encoding(encoding)
218:           else
219:             conn.async_exec("set client_encoding to '#{encoding}'")
220:           end
221:         end
222: 
223:         connection_configuration_sqls(opts).each{|sql| conn.execute(sql)}
224:         conn
225:       end

Always false, support was moved to pg_extended_date_support extension. Needs to stay defined here so that sequel_pg works.

[Source]

     # File lib/sequel/adapters/postgres.rb, line 229
229:       def convert_infinite_timestamps
230:         false
231:       end

Enable pg_extended_date_support extension if symbol or string is given.

[Source]

     # File lib/sequel/adapters/postgres.rb, line 234
234:       def convert_infinite_timestamps=(v)
235:         case v
236:         when Symbol, String, true
237:           extension(:pg_extended_date_support)
238:           self.convert_infinite_timestamps = v
239:         end
240:       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.

[Source]

     # File lib/sequel/adapters/postgres.rb, line 377
377:         def copy_into(table, opts=OPTS)
378:           data = opts[:data]
379:           data = Array(data) if data.is_a?(String)
380: 
381:           if block_given? && data
382:             raise Error, "Cannot provide both a :data option and a block to copy_into"
383:           elsif !block_given? && !data
384:             raise Error, "Must provide either a :data option or a block to copy_into"
385:           end
386: 
387:           synchronize(opts[:server]) do |conn|
388:             conn.execute(copy_into_sql(table, opts))
389:             begin
390:               if block_given?
391:                 while buf = yield
392:                   conn.put_copy_data(buf)
393:                 end
394:               else
395:                 data.each{|buff| conn.put_copy_data(buff)}
396:               end
397:             rescue Exception => e
398:               conn.put_copy_end("ruby exception occurred while copying data into PostgreSQL")
399:             ensure
400:               conn.put_copy_end unless e
401:               while res = conn.get_result
402:                 raise e if e
403:                 check_database_errors{res.check}
404:               end
405:             end
406:           end 
407:         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+. This should be the full COPY statement passed to PostgreSQL, not just the SELECT query. If a string is given, the :format and :options options are ignored.
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.

[Source]

     # File lib/sequel/adapters/postgres.rb, line 327
327:         def copy_table(table, opts=OPTS)
328:           synchronize(opts[:server]) do |conn|
329:             conn.execute(copy_table_sql(table, opts))
330:             begin
331:               if block_given?
332:                 while buf = conn.get_copy_data
333:                   yield buf
334:                 end
335:                 b = nil
336:               else
337:                 b = String.new
338:                 b << buf while buf = conn.get_copy_data
339:               end
340: 
341:               res = conn.get_last_result
342:               if !res || res.result_status != 1
343:                 raise PG::NotAllCopyDataRetrieved, "Not all COPY data retrieved"
344:               end
345: 
346:               b
347:             rescue => e
348:               raise_error(e, :disconnect=>true)
349:             ensure
350:               if buf && !e
351:                 raise DatabaseDisconnectError, "disconnecting as a partial COPY may leave the connection in an unusable state"
352:               end
353:             end
354:           end 
355:         end

[Source]

     # File lib/sequel/adapters/postgres.rb, line 242
242:       def disconnect_connection(conn)
243:         conn.finish
244:       rescue PGError, IOError
245:         nil
246:       end

Return a hash of information about the related PGError (or Sequel::DatabaseError that wraps a PGError), with the following entries (any of which may be nil):

: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
:severity :The severity of the error (e.g. "ERROR")
:sql_state :The SQL state code related to the error
:message_primary :A single line message related to the error
:message_detail :Any detail supplementing the primary message
:message_hint :Possible suggestion about how to fix the problem
:statement_position :Character offset in statement submitted by client where error occurred (starting at 1)
:internal_position :Character offset in internal statement where error occurred (starting at 1)
:internal_query :Text of internally-generated statement where error occurred
:source_file :PostgreSQL source file where the error occurred
:source_line :Line number of PostgreSQL source file where the error occurred
:source_function :Function in PostgreSQL source file where the error occurred

This requires a PostgreSQL 9.3+ server and 9.3+ client library, and ruby-pg 0.16.0+ to be supported.

[Source]

     # File lib/sequel/adapters/postgres.rb, line 271
271:         def error_info(e)
272:           e = e.wrapped_exception if e.is_a?(DatabaseError)
273:           r = e.result
274:           {
275:             :schema => r.error_field(::PG::PG_DIAG_SCHEMA_NAME),
276:             :table => r.error_field(::PG::PG_DIAG_TABLE_NAME),
277:             :column => r.error_field(::PG::PG_DIAG_COLUMN_NAME),
278:             :constraint => r.error_field(::PG::PG_DIAG_CONSTRAINT_NAME),
279:             :type => r.error_field(::PG::PG_DIAG_DATATYPE_NAME),
280:             :severity => r.error_field(::PG::PG_DIAG_SEVERITY),
281:             :sql_state => r.error_field(::PG::PG_DIAG_SQLSTATE),
282:             :message_primary => r.error_field(::PG::PG_DIAG_MESSAGE_PRIMARY),
283:             :message_detail => r.error_field(::PG::PG_DIAG_MESSAGE_DETAIL),
284:             :message_hint => r.error_field(::PG::PG_DIAG_MESSAGE_HINT),
285:             :statement_position => r.error_field(::PG::PG_DIAG_STATEMENT_POSITION),
286:             :internal_position => r.error_field(::PG::PG_DIAG_INTERNAL_POSITION),
287:             :internal_query => r.error_field(::PG::PG_DIAG_INTERNAL_QUERY),
288:             :source_file => r.error_field(::PG::PG_DIAG_SOURCE_FILE),
289:             :source_line => r.error_field(::PG::PG_DIAG_SOURCE_LINE),
290:             :source_function => r.error_field(::PG::PG_DIAG_SOURCE_FUNCTION)
291:           }
292:         end

[Source]

     # File lib/sequel/adapters/postgres.rb, line 295
295:       def execute(sql, opts=OPTS, &block)
296:         synchronize(opts[:server]){|conn| check_database_errors{_execute(conn, sql, opts, &block)}}
297:       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:

  • the channel the notification was sent to (as a string)
  • the backend pid of the notifier (as an integer),
  • and the payload of the notification (as a string or nil).

[Source]

     # File lib/sequel/adapters/postgres.rb, line 432
432:         def listen(channels, opts=OPTS, &block)
433:           check_database_errors do
434:             synchronize(opts[:server]) do |conn|
435:               begin
436:                 channels = Array(channels)
437:                 channels.each do |channel|
438:                   sql = "LISTEN ".dup
439:                   dataset.send(:identifier_append, sql, channel)
440:                   conn.execute(sql)
441:                 end
442:                 opts[:after_listen].call(conn) if opts[:after_listen]
443:                 timeout = opts[:timeout]
444:                 if timeout
445:                   timeout_block = timeout.respond_to?(:call) ? timeout : proc{timeout}
446:                 end
447: 
448:                 if l = opts[:loop]
449:                   raise Error, 'calling #listen with :loop requires a block' unless block
450:                   loop_call = l.respond_to?(:call)
451:                   catch(:stop) do
452:                     while true
453:                       t = timeout_block ? [timeout_block.call] : []
454:                       conn.wait_for_notify(*t, &block)
455:                       l.call(conn) if loop_call
456:                     end
457:                   end
458:                   nil
459:                 else
460:                   t = timeout_block ? [timeout_block.call] : []
461:                   conn.wait_for_notify(*t, &block)
462:                 end
463:               ensure
464:                 conn.execute("UNLISTEN *")
465:               end
466:             end
467:           end
468:         end

[Validate]