Class: Sequel::Postgres::Adapter

Inherits:
PGconn
  • Object
show all
Defined in:
lib/sequel/adapters/postgres.rb

Overview

PGconn subclass for connection specific methods used with the pg or postgres-pr driver.

Defined Under Namespace

Classes: PGresult

Constant Summary collapse

DISCONNECT_ERROR_CLASSES =

The underlying exception classes to reraise as disconnect errors instead of regular database errors.

[IOError, Errno::EPIPE, Errno::ECONNRESET]
DISCONNECT_ERROR_RE =

Since exception class based disconnect checking may not work, also trying parsing the exception message to look for disconnect errors.

/\A#{Regexp.union(disconnect_errors)}/
CONNECTION_OK =

Make postgres-pr look like pg

-1

Instance Attribute Summary collapse

Instance Method Summary collapse

Instance Attribute Details

#prepared_statements ⇒ Object (readonly)

Hash of prepared statements for this connection. Keys are string names of the server side prepared statement, and values are SQL strings.



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# File 'lib/sequel/adapters/postgres.rb', line 72

def prepared_statements
  @prepared_statements
end

Instance Method Details

#async_exec(sql) ⇒ Object 



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# File 'lib/sequel/adapters/postgres.rb', line 91

def async_exec(sql)
  PGresult.new(@conn.query(sql))
end

#block(timeout = nil) ⇒ Object 



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# File 'lib/sequel/adapters/postgres.rb', line 95

def block(timeout=nil)
end

#check_disconnect_errors ⇒ Object

Raise a Sequel::DatabaseDisconnectError if a one of the disconnect error classes is raised, or a PGError is raised and the connection status cannot be determined or it is not OK.



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# File 'lib/sequel/adapters/postgres.rb', line 114

def check_disconnect_errors
  begin
    yield
  rescue *DISCONNECT_ERROR_CLASSES => e
    disconnect = true
    raise(Sequel.convert_exception_class(e, Sequel::DatabaseDisconnectError))
  rescue PGError => e
    disconnect = false
    begin
      s = status
    rescue PGError
      disconnect = true
    end
    status_ok = (s == Adapter::CONNECTION_OK)
    disconnect ||= !status_ok
    disconnect ||= e.message =~ DISCONNECT_ERROR_RE
    disconnect ? raise(Sequel.convert_exception_class(e, Sequel::DatabaseDisconnectError)) : raise
  ensure
    block if status_ok && !disconnect
  end
end

#escape_bytea(str) ⇒ Object

Escape bytea values. Uses historical format instead of hex format for maximum compatibility.



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# File 'lib/sequel/adapters/postgres.rb', line 79

def escape_bytea(str)
  str.gsub(/[\000-\037\047\134\177-\377]/n){|b| "\\#{sprintf('%o', b.each_byte{|x| break x}).rjust(3, '0')}"}
end

#escape_string(str) ⇒ Object

Escape strings by doubling apostrophes. This only works if standard conforming strings are used.



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# File 'lib/sequel/adapters/postgres.rb', line 85

def escape_string(str)
  str.gsub("'", "''")
end

#execute(sql, args = nil) ⇒ Object

Execute the given SQL with this connection. If a block is given, yield the results, otherwise, return the number of changed rows.



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# File 'lib/sequel/adapters/postgres.rb', line 138

def execute(sql, args=nil)
  args = args.map{|v| @db.bound_variable_arg(v, self)} if args
  q = check_disconnect_errors{execute_query(sql, args)}
  begin
    block_given? ? yield(q) : q.cmd_tuples
  ensure
    q.clear if q && q.respond_to?(:clear)
  end
end

#status ⇒ Object 



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# File 'lib/sequel/adapters/postgres.rb', line 98

def status
  CONNECTION_OK
end