SUMMARY STEPS TO REPRODUCE 1. Open krunner 2. type some seach term (>= 3 letters) 3. close krunner again OBSERVED RESULT After closing, each time 4 warning messages are added to the journal: QSqlDatabasePrivate::removeDatabase: connection '.../places.sqlite' is still in use, all queries will cease to work. QSqlDatabasePrivate::addDatabase: duplicate connection name '.../places.sqlite', old connection removed. QSqlDatabasePrivate::removeDatabase: connection '.../favicons.sqlite' is still in use, all queries will cease to work. QSqlDatabasePrivate::addDatabase: duplicate connection name '.../favicons.sqlite', old connection removed. EXPECTED RESULT Warnings should be fixed SOFTWARE VERSIONS (available in About System) KDE Plasma Version: 5.14.2 KDE Frameworks Version: 5.51 Qt Version: 5.11.2 ADDITIONAL INFORMATION
Git commit 145caeac105043d2d0bfba40717e9ed336471ccf by Stefan Brüns. Committed on 14/11/2018 at 23:55. Pushed by bruns into branch 'master'. [Bookmarks Runner] Open database connection in the query thread Summary: QSqlDatabase connection instances are global reference counted objects which can be crated using the QSqlDatabase::addDatabase(...) method and later retrieved with QSqlDatabase::database(connectionname). Connections should only be used from a single thread, and should be cleaned up with QSD::removeDatabase(name), which implicitly closes the connection when the last reference is removed. Currently, the same connection (name) is reused over all threads, and the connection is only removed implicitly by replacing it via addDatabase(). This leads to warnings, i.e.: "QSqlDatabasePrivate::addDatabase: duplicate connection name '...', old connection removed." As one reference is held by the m_db member, the implicit removal triggers another warning: "QSqlDatabasePrivate::removeDatabase: connection '..." is still in use, all queries will cease to work." According to the documentation, "It is highly recommended that you do not keep a copy of the QSqlDatabase around as a member of a class, as this will prevent the instance from being correctly cleaned up on shutdown." There is no need to keep a reference using a member variable, as retrieving an open connection via QSqlDatabase::database(...) is cheap. Create a per-thread DB connection on first use, and remove the connections when the FetchSqlite instance is torn down. Delaying the open is beneficial for the favicon instance, which may be unused when the icon is already cached on disk. See also T9626. Test Plan: execute a query in krunner 1. Results are as expected 2. The 'QSqlDatabasePrivate::removeDatabase: connection ... is still in use, all queries will cease to work.' warning no longer appears 3. The 'QSqlDatabasePrivate::addDatabase: duplicate connection name ..., old connection removed' warning no longer appears Reviewers: #frameworks, mart Reviewed By: mart Subscribers: plasma-devel Tags: #plasma Differential Revision: https://phabricator.kde.org/D16409 M +43 -16 runners/bookmarks/fetchsqlite.cpp M +0 -1 runners/bookmarks/fetchsqlite.h https://commits.kde.org/plasma-workspace/145caeac105043d2d0bfba40717e9ed336471ccf