class Sequel::Postgres::Database

Constants

DATABASE_ERROR_CLASSES

Public Instance Methods

bound_variable_arg(arg, conn) click to toggle source

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.

    # File lib/sequel/adapters/postgres.rb
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
connect(server) click to toggle source

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
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
convert_infinite_timestamps() click to toggle source

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

    # File lib/sequel/adapters/postgres.rb
229 def convert_infinite_timestamps
230   false
231 end
convert_infinite_timestamps=(v) click to toggle source

Enable pg_extended_date_support extension if symbol or string is given.

    # File lib/sequel/adapters/postgres.rb
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(table, opts=OPTS) click to toggle source

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
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(table, opts=OPTS) { |buf| ... } click to toggle source

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.

    # File lib/sequel/adapters/postgres.rb
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
disconnect_connection(conn) click to toggle source
    # File lib/sequel/adapters/postgres.rb
242 def disconnect_connection(conn)
243   conn.finish
244 rescue PGError, IOError
245   nil
246 end
error_info(e) click to toggle source

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.

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

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).

    # File lib/sequel/adapters/postgres.rb
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

Private Instance Methods

_execute(conn, sql, opts, &block) click to toggle source

Execute the given SQL string or prepared statement on the connection object.

    # File lib/sequel/adapters/postgres.rb
474 def _execute(conn, sql, opts, &block)
475   if sql.is_a?(Symbol)
476     execute_prepared_statement(conn, sql, opts, &block)
477   else
478     conn.execute(sql, opts[:arguments], &block)
479   end
480 end
_execute_prepared_statement(conn, ps_name, args, opts) click to toggle source

Execute the prepared statement name with the given arguments on the connection.

    # File lib/sequel/adapters/postgres.rb
483 def _execute_prepared_statement(conn, ps_name, args, opts)
484   conn.exec_prepared(ps_name, args)
485 end
adapter_initialize() click to toggle source

Add the primary_keys and primary_key_sequences instance variables, so we can get the correct return values for inserted rows.

    # File lib/sequel/adapters/postgres.rb
489 def adapter_initialize
490   @use_iso_date_format = typecast_value_boolean(@opts.fetch(:use_iso_date_format, true))
491   initialize_postgres_adapter
492   add_conversion_proc(17, method(:unescape_bytea)) if USES_PG
493   add_conversion_proc(1082, TYPE_TRANSLATOR.method(:date)) if @use_iso_date_format
494   self.convert_infinite_timestamps = @opts[:convert_infinite_timestamps]
495 end
check_database_errors() { || ... } click to toggle source

Convert exceptions raised from the block into DatabaseErrors.

    # File lib/sequel/adapters/postgres.rb
498 def check_database_errors
499   begin
500     yield
501   rescue => e
502     raise_error(e, :classes=>database_error_classes)
503   end
504 end
connection_configuration_sqls(opts=@opts) click to toggle source

Set the DateStyle to ISO if configured, for faster date parsing.

    # File lib/sequel/adapters/postgres.rb
507 def connection_configuration_sqls(opts=@opts)
508   sqls = super
509   sqls << "SET DateStyle = 'ISO'" if @use_iso_date_format
510   sqls
511 end
database_error_classes() click to toggle source
    # File lib/sequel/adapters/postgres.rb
520 def database_error_classes
521   DATABASE_ERROR_CLASSES
522 end
database_exception_sqlstate(exception, opts) click to toggle source
    # File lib/sequel/adapters/postgres.rb
530 def database_exception_sqlstate(exception, opts)
531   if exception.respond_to?(:result) && (result = exception.result)
532     result.error_field(PGresult::PG_DIAG_SQLSTATE)
533   end
534 end
dataset_class_default() click to toggle source
    # File lib/sequel/adapters/postgres.rb
536 def dataset_class_default
537   Dataset
538 end
disconnect_error?(exception, opts) click to toggle source
Calls superclass method Sequel::Database#disconnect_error?
    # File lib/sequel/adapters/postgres.rb
524 def disconnect_error?(exception, opts)
525   super ||
526     Adapter::DISCONNECT_ERROR_CLASSES.any?{|klass| exception.is_a?(klass)} ||
527     exception.message =~ Adapter::DISCONNECT_ERROR_RE
528 end
execute_prepared_statement(conn, name, opts=OPTS) { |q| ... } click to toggle source

Execute the prepared statement with the given name on an available connection, using the given args. If the connection has not prepared a statement with the given name yet, prepare it. If the connection has prepared a statement with the same name and different SQL, deallocate that statement first and then prepare this statement. If a block is given, yield the result, otherwise, return the number of rows changed.

    # File lib/sequel/adapters/postgres.rb
547 def execute_prepared_statement(conn, name, opts=OPTS, &block)
548   ps = prepared_statement(name)
549   sql = ps.prepared_sql
550   ps_name = name.to_s
551 
552   if args = opts[:arguments]
553     args = args.map{|arg| bound_variable_arg(arg, conn)}
554   end
555 
556   unless conn.prepared_statements[ps_name] == sql
557     conn.execute("DEALLOCATE #{ps_name}") if conn.prepared_statements.include?(ps_name)
558     conn.check_disconnect_errors{log_connection_yield("PREPARE #{ps_name} AS #{sql}", conn){conn.prepare(ps_name, sql)}}
559     conn.prepared_statements[ps_name] = sql
560   end
561 
562   log_sql = "EXECUTE #{ps_name}"
563   if ps.log_sql
564     log_sql += " ("
565     log_sql << sql
566     log_sql << ")"
567   end
568 
569   q = conn.check_disconnect_errors{log_connection_yield(log_sql, conn, args){_execute_prepared_statement(conn, ps_name, args, opts)}}
570   begin
571     block_given? ? yield(q) : q.cmd_tuples
572   ensure
573     q.clear if q && q.respond_to?(:clear)
574   end
575 end
log_connection_execute(conn, sql) click to toggle source

Don't log, since logging is done by the underlying connection.

    # File lib/sequel/adapters/postgres.rb
578 def log_connection_execute(conn, sql)
579   conn.execute(sql)
580 end
rollback_transaction(conn, opts=OPTS) click to toggle source
Calls superclass method Sequel::Database#rollback_transaction
    # File lib/sequel/adapters/postgres.rb
582 def rollback_transaction(conn, opts=OPTS)
583   super unless conn.transaction_status == 0
584 end
unescape_bytea(s) click to toggle source
    # File lib/sequel/adapters/postgres.rb
514 def unescape_bytea(s)
515   ::Sequel::SQL::Blob.new(Adapter.unescape_bytea(s))
516 end