Description:
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PDOException::getCode() returns the SQLSTATE instead of the error code.

For example a var_dump of a random PDOException:

object(PDOException)[97]
  protected 'message' => string 'SQLSTATE[40001]: Serialization failure: 1213 
Deadlock found when trying to get lock; try restarting transaction' (length=111)
  private 'string' (Exception) => string '' (length=0)
  protected 'code' => string '40001' (length=5)

then the 'code' should not be the SQLSTATE (40001) but the error code (1213). My 
reason for this is that the SQLSTATE may not be unique, the error code is.

For more info: http://dev.mysql.com/doc/refman/5.5/en/error-messages-server.html

Test script:
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Try to get a random PDOException with an invalid query.