Exception thrown when the database server encounters a problem while processing your query. More...

#include <exceptions.h>

Inheritance diagram for mysqlpp::BadQuery:

Collaboration diagram for mysqlpp::BadQuery:

[legend]

Public Member Functions
	BadQuery (const char *w="", int e=0)
	Create exception object. More...

	BadQuery (const std::string &w, int e=0)
	Create exception object. More...

int	errnum () const
	Return the error number corresponding to the error message returned by what() More...

Public Member Functions inherited from mysqlpp::Exception
	Exception (const Exception &e) MAY_THROW()
	Create exception object as copy of another.

Exception &	operator= (const Exception &rhs) throw ()
	Assign another exception object's contents to this one.

	~Exception () throw ()
	Destroy exception object.

virtual const char *	what () const throw ()
	Returns explanation of why exception was thrown.

Additional Inherited Members
Protected Member Functions inherited from mysqlpp::Exception
	Exception (const char *w="") throw ()
	Create exception object.

	Exception (const std::string &w) throw ()
	Create exception object.

Protected Attributes inherited from mysqlpp::Exception
std::string	what_
	explanation of why exception was thrown

Detailed Description

Exception thrown when the database server encounters a problem while processing your query.

Unlike most other MySQL++ exceptions, which carry just an error message, this type carries an error number to preserve Connection::errnum()'s return value at the point the exception is thrown. We do this because when using the Transaction class, the rollback process that occurs during stack unwinding issues a query to the database server, overwriting the error value. This rollback should always succeed, so this effect can fool code that relies on Connection::errnum() into believing that there was no error.

Beware that in older versions of MySQL++, this was effectively the generic exception type. (This is most especially true in v1.7.x, but it continued to a lesser extent through the v2.x series.) When converting old code to new versions of MySQL++, it's therefore possible to get seemingly "new" exceptions thrown, which could crash your program if you don't also catch a more generic type like mysqlpp::Exception or std::exception.

Constructor & Destructor Documentation

◆ BadQuery() [1/2]

mysqlpp::BadQuery::BadQuery	(	const char *	w = `""`,
		int	e = `0`
	)

inlineexplicit

Create exception object.

Parameters

w	explanation for why the exception was thrown
e	the error number from the underlying database API

◆ BadQuery() [2/2]

mysqlpp::BadQuery::BadQuery	(	const std::string &	w,
		int	e = `0`
	)

inlineexplicit

Create exception object.

Parameters

w	explanation for why the exception was thrown
e	the error number from the underlying database API

Member Function Documentation

◆ errnum()

int mysqlpp::BadQuery::errnum ( ) const

inline

Return the error number corresponding to the error message returned by what()

This may return the same value as Connection::errnum(), but not always. See the overview documentation for this class for the reason for the difference.

The documentation for this class was generated from the following file:

exceptions.h