27.7.6.3 mysql_change_user()
my_bool mysql_change_user(MYSQL *mysql, const char *user, const char *password, const char *db)
Changes the user and causes the database specified by db
to become the default (current) database on the connection specified by mysql
. In subsequent queries, this database is the default for table references that include no explicit database specifier.
mysql_change_user()
fails if the connected user cannot be authenticated or does not have permission to use the database. In this case, the user and database are not changed.
Pass a db
parameter of NULL
if you do not want to have a default database.
This function resets the session state as if one had done a new connect and reauthenticated. (See Section 27.7.19, “C API Automatic Reconnection Control”.) It always performs a ROLLBACK
of any active transactions, closes and drops all temporary tables, and unlocks all locked tables. Session system variables are reset to the values of the corresponding global system variables. Prepared statements are released and HANDLER
variables are closed. Locks acquired with GET_LOCK()
are released. These effects occur even if the user did not change.
To reset the connection state in a more lightweight manner without changing the user, use mysql_reset_connection()
.
The same that you can get from mysql_real_connect()
, plus:
Commands were executed in an improper order.
The MySQL server has gone away.
The connection to the server was lost during the query.
An unknown error occurred.
The MySQL server does not implement this command (probably an old server).
The user or password was wrong.
The database did not exist.
The user did not have access rights to the database.
The database name was too long.