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
165 def bound_variable_arg(arg, conn)
166   case arg
167   when Sequel::SQL::Blob
168     {:value=>arg, :type=>17, :format=>1}
169   when DateTime, Time
170     literal(arg)
171   else
172     arg
173   end
174 end
call_procedure(name, *args) click to toggle source

Call a procedure with the given name and arguments. Returns a hash if the procedure returns a value, and nil otherwise. Example:

DB.call_procedure(:foo, 1, 2)
# CALL foo(1, 2)
    # File lib/sequel/adapters/postgres.rb
181 def call_procedure(name, *args)
182   dataset.send(:call_procedure, name, args)
183 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
192 def connect(server)
193   opts = server_opts(server)
194   if USES_PG
195     connection_params = {
196       :host => opts[:host],
197       :port => opts[:port],
198       :dbname => opts[:database],
199       :user => opts[:user],
200       :password => opts[:password],
201       :connect_timeout => opts[:connect_timeout] || 20,
202       :sslmode => opts[:sslmode],
203       :sslrootcert => opts[:sslrootcert]
204     }.delete_if { |key, value| blank_object?(value) }
205     connection_params.merge!(opts[:driver_options]) if opts[:driver_options]
206     conn = Adapter.connect(opts[:conn_str] || connection_params)
207 
208     conn.instance_variable_set(:@prepared_statements, {})
209 
210     if receiver = opts[:notice_receiver]
211       conn.set_notice_receiver(&receiver)
212     end
213   else
214     unless typecast_value_boolean(@opts.fetch(:force_standard_strings, true))
215       raise Error, "Cannot create connection using postgres-pr unless force_standard_strings is set"
216     end
217 
218     conn = Adapter.connect(
219       (opts[:host] unless blank_object?(opts[:host])),
220       opts[:port] || 5432,
221       nil, '',
222       opts[:database],
223       opts[:user],
224       opts[:password]
225     )
226   end
227 
228   conn.instance_variable_set(:@db, self)
229   if USES_PG && conn.respond_to?(:type_map_for_queries=) && defined?(PG_QUERY_TYPE_MAP)
230     conn.type_map_for_queries = PG_QUERY_TYPE_MAP
231   end
232 
233   if encoding = opts[:encoding] || opts[:charset]
234     if conn.respond_to?(:set_client_encoding)
235       conn.set_client_encoding(encoding)
236     else
237       conn.async_exec("set client_encoding to '#{encoding}'")
238     end
239   end
240 
241   connection_configuration_sqls(opts).each{|sql| conn.execute(sql)}
242   conn
243 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
247 def convert_infinite_timestamps
248   false
249 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
252 def convert_infinite_timestamps=(v)
253   case v
254   when Symbol, String, true
255     extension(:pg_extended_date_support)
256     self.convert_infinite_timestamps = v
257   end
258 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
395 def copy_into(table, opts=OPTS)
396   data = opts[:data]
397   data = Array(data) if data.is_a?(String)
398 
399   if block_given? && data
400     raise Error, "Cannot provide both a :data option and a block to copy_into"
401   elsif !block_given? && !data
402     raise Error, "Must provide either a :data option or a block to copy_into"
403   end
404 
405   synchronize(opts[:server]) do |conn|
406     conn.execute(copy_into_sql(table, opts))
407     begin
408       if block_given?
409         while buf = yield
410           conn.put_copy_data(buf)
411         end
412       else
413         data.each{|buff| conn.put_copy_data(buff)}
414       end
415     rescue Exception => e
416       conn.put_copy_end("ruby exception occurred while copying data into PostgreSQL")
417     ensure
418       conn.put_copy_end unless e
419       while res = conn.get_result
420         raise e if e
421         check_database_errors{res.check}
422       end
423     end
424   end 
425 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
345 def copy_table(table, opts=OPTS)
346   synchronize(opts[:server]) do |conn|
347     conn.execute(copy_table_sql(table, opts))
348     begin
349       if block_given?
350         while buf = conn.get_copy_data
351           yield buf
352         end
353         b = nil
354       else
355         b = String.new
356         b << buf while buf = conn.get_copy_data
357       end
358 
359       res = conn.get_last_result
360       if !res || res.result_status != 1
361         raise PG::NotAllCopyDataRetrieved, "Not all COPY data retrieved"
362       end
363 
364       b
365     rescue => e
366       raise_error(e, :disconnect=>true)
367     ensure
368       if buf && !e
369         raise DatabaseDisconnectError, "disconnecting as a partial COPY may leave the connection in an unusable state"
370       end
371     end
372   end 
373 end
disconnect_connection(conn) click to toggle source
    # File lib/sequel/adapters/postgres.rb
260 def disconnect_connection(conn)
261   conn.finish
262 rescue PGError, IOError
263   nil
264 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
289 def error_info(e)
290   e = e.wrapped_exception if e.is_a?(DatabaseError)
291   r = e.result
292   {
293     :schema => r.error_field(::PG::PG_DIAG_SCHEMA_NAME),
294     :table => r.error_field(::PG::PG_DIAG_TABLE_NAME),
295     :column => r.error_field(::PG::PG_DIAG_COLUMN_NAME),
296     :constraint => r.error_field(::PG::PG_DIAG_CONSTRAINT_NAME),
297     :type => r.error_field(::PG::PG_DIAG_DATATYPE_NAME),
298     :severity => r.error_field(::PG::PG_DIAG_SEVERITY),
299     :sql_state => r.error_field(::PG::PG_DIAG_SQLSTATE),
300     :message_primary => r.error_field(::PG::PG_DIAG_MESSAGE_PRIMARY),
301     :message_detail => r.error_field(::PG::PG_DIAG_MESSAGE_DETAIL),
302     :message_hint => r.error_field(::PG::PG_DIAG_MESSAGE_HINT),
303     :statement_position => r.error_field(::PG::PG_DIAG_STATEMENT_POSITION),
304     :internal_position => r.error_field(::PG::PG_DIAG_INTERNAL_POSITION),
305     :internal_query => r.error_field(::PG::PG_DIAG_INTERNAL_QUERY),
306     :source_file => r.error_field(::PG::PG_DIAG_SOURCE_FILE),
307     :source_line => r.error_field(::PG::PG_DIAG_SOURCE_LINE),
308     :source_function => r.error_field(::PG::PG_DIAG_SOURCE_FUNCTION)
309   }
310 end
execute(sql, opts=OPTS, &block) click to toggle source
    # File lib/sequel/adapters/postgres.rb
313 def execute(sql, opts=OPTS, &block)
314   synchronize(opts[:server]){|conn| check_database_errors{_execute(conn, sql, opts, &block)}}
315 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
450 def listen(channels, opts=OPTS, &block)
451   check_database_errors do
452     synchronize(opts[:server]) do |conn|
453       begin
454         channels = Array(channels)
455         channels.each do |channel|
456           sql = "LISTEN ".dup
457           dataset.send(:identifier_append, sql, channel)
458           conn.execute(sql)
459         end
460         opts[:after_listen].call(conn) if opts[:after_listen]
461         timeout = opts[:timeout]
462         if timeout
463           timeout_block = timeout.respond_to?(:call) ? timeout : proc{timeout}
464         end
465 
466         if l = opts[:loop]
467           raise Error, 'calling #listen with :loop requires a block' unless block
468           loop_call = l.respond_to?(:call)
469           catch(:stop) do
470             while true
471               t = timeout_block ? [timeout_block.call] : []
472               conn.wait_for_notify(*t, &block)
473               l.call(conn) if loop_call
474             end
475           end
476           nil
477         else
478           t = timeout_block ? [timeout_block.call] : []
479           conn.wait_for_notify(*t, &block)
480         end
481       ensure
482         conn.execute("UNLISTEN *")
483       end
484     end
485   end
486 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
492 def _execute(conn, sql, opts, &block)
493   if sql.is_a?(Symbol)
494     execute_prepared_statement(conn, sql, opts, &block)
495   else
496     conn.execute(sql, opts[:arguments], &block)
497   end
498 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
501 def _execute_prepared_statement(conn, ps_name, args, opts)
502   conn.exec_prepared(ps_name, args)
503 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
507 def adapter_initialize
508   @use_iso_date_format = typecast_value_boolean(@opts.fetch(:use_iso_date_format, true))
509   initialize_postgres_adapter
510   add_conversion_proc(17, method(:unescape_bytea)) if USES_PG
511   add_conversion_proc(1082, TYPE_TRANSLATOR_DATE) if @use_iso_date_format
512   self.convert_infinite_timestamps = @opts[:convert_infinite_timestamps]
513 end
check_database_errors() { || ... } click to toggle source

Convert exceptions raised from the block into DatabaseErrors.

    # File lib/sequel/adapters/postgres.rb
516 def check_database_errors
517   begin
518     yield
519   rescue => e
520     raise_error(e, :classes=>database_error_classes)
521   end
522 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
525 def connection_configuration_sqls(opts=@opts)
526   sqls = super
527   sqls << "SET DateStyle = 'ISO'" if @use_iso_date_format
528   sqls
529 end
database_error_classes() click to toggle source
    # File lib/sequel/adapters/postgres.rb
538 def database_error_classes
539   DATABASE_ERROR_CLASSES
540 end
database_exception_sqlstate(exception, opts) click to toggle source
    # File lib/sequel/adapters/postgres.rb
548 def database_exception_sqlstate(exception, opts)
549   if exception.respond_to?(:result) && (result = exception.result)
550     result.error_field(PGresult::PG_DIAG_SQLSTATE)
551   end
552 end
dataset_class_default() click to toggle source
    # File lib/sequel/adapters/postgres.rb
554 def dataset_class_default
555   Dataset
556 end
disconnect_error?(exception, opts) click to toggle source
Calls superclass method Sequel::Database#disconnect_error?
    # File lib/sequel/adapters/postgres.rb
542 def disconnect_error?(exception, opts)
543   super ||
544     Adapter::DISCONNECT_ERROR_CLASSES.any?{|klass| exception.is_a?(klass)} ||
545     exception.message =~ Adapter::DISCONNECT_ERROR_RE
546 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
565 def execute_prepared_statement(conn, name, opts=OPTS, &block)
566   ps = prepared_statement(name)
567   sql = ps.prepared_sql
568   ps_name = name.to_s
569 
570   if args = opts[:arguments]
571     args = args.map{|arg| bound_variable_arg(arg, conn)}
572   end
573 
574   unless conn.prepared_statements[ps_name] == sql
575     conn.execute("DEALLOCATE #{ps_name}") if conn.prepared_statements.include?(ps_name)
576     conn.check_disconnect_errors{log_connection_yield("PREPARE #{ps_name} AS #{sql}", conn){conn.prepare(ps_name, sql)}}
577     conn.prepared_statements[ps_name] = sql
578   end
579 
580   log_sql = "EXECUTE #{ps_name}"
581   if ps.log_sql
582     log_sql += " ("
583     log_sql << sql
584     log_sql << ")"
585   end
586 
587   q = conn.check_disconnect_errors{log_connection_yield(log_sql, conn, args){_execute_prepared_statement(conn, ps_name, args, opts)}}
588   begin
589     block_given? ? yield(q) : q.cmd_tuples
590   ensure
591     q.clear if q && q.respond_to?(:clear)
592   end
593 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
596 def log_connection_execute(conn, sql)
597   conn.execute(sql)
598 end
rollback_transaction(conn, opts=OPTS) click to toggle source
Calls superclass method Sequel::Database#rollback_transaction
    # File lib/sequel/adapters/postgres.rb
600 def rollback_transaction(conn, opts=OPTS)
601   super unless conn.transaction_status == 0
602 end
unescape_bytea(s) click to toggle source
    # File lib/sequel/adapters/postgres.rb
532 def unescape_bytea(s)
533   ::Sequel::SQL::Blob.new(Adapter.unescape_bytea(s))
534 end