Posted on 2010-09-12 09:16
Tommy Liang 閱讀(604)
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在如下系列中：
1、QSqlQuery q("select count(*) from sometable where name=:name");
...
2、QSqlDatabase::database().transaction();
....
在1和2之間如果不清除q，是會鎖死的，答案在這里：
bool QSqlDatabase::commit ()
Commits a transaction to the database if the driver supports transactions and a transaction() has been started. Returns true if the operation succeeded. Otherwise it returns false.
Note: For some databases, the commit will fail and return false if there is an active query using the database for a SELECT. Make the query inactive before doing the commit.
Call lastError() to get information about errors.
See also QSqlQuery::isActive(), QSqlDriver::hasFeature(), and rollback().