There were numerous memory leaks in plugin's code and associated code.
During typical run of MTR tests it leaked around 65 megabytes of
objects. As a result they may severely affect long-lived connections.
This patch fixes (almost) all leaks found in the plugin. The exceptions
are two leaks associated with SHOW CREATE TABLE columnstore_table and
getting information of columns of columnstore-handled table. These
should be fixed on the server side and work is on the way.
Original SH implementation sends the result set back to the client
thus it can't be used in INSERT..SELECT, SELECT INTO OUTFILE,CREATE
TABLE AS SELECT etc.
CLX-77 feature has been backported into MDB to enable SH to run
query part of the mentioned queries.
Disabled 4th if block in buildOuterJoin to handle non-optimized MDB query
structures.
Broke getSelectPlan into pieces: processFrom, processWhere.
MCOL-3593 UNION processing depends on two flags isUnion that comes as
arg of getSelectPlan and unionSel that is a local variable in
getSelectPlan. Modularization of getSelectPlan broke the mechanizm.
This patch is supposed to partially fix it.
MCOL-3593 Removed unused if condition from buildOuterJoin that allows
unsupported construct subquery in ON expression.
Fixed an improper if condition that ignors tableMap entries w/o condition
in external_lock thus external_lock doesn't clean up when the query
finishes.
Fixed wrong logging for queries processed in tableMode. Now rnd_init
properly sends queryText down to ExeMgr to be logged.
MCOL-3593 Unused attribute FromSubQuery::fFromSub was removed.
getSelectPlan has been modularized into: setExecutionParams,
processFrom, processWhere. SELECT, HAVING, GROUP BY, ORDER BY
still lives in getSelectPlan.
Copied optimization function simplify_joins_ into our pushdown
code to provide the plugin code with some rewrites from MDB it
expects.
The columnstore_processing_handlers_fallback session variable
has been removed thus CS can't fallback from SH to partial
execution paths, e.g. DH, GBH or plugin API.
MCOL-3602 Moved MDB optimizer rewrites into a separate file.
Add SELECT_LEX::optimize_unflattened_subqueries() call to fix IN
into EXISTS rewrite for semi-JOINs with subqueries.
disable_indices_for_CEJ() add index related hints to disable
index access methods in Cross Engine Joins.
create_SH() now flattens JOIN that has both physical tables and
views. This fixes most of views related tests in the regression.
Fix crash in ha_calpont_impl_close_connection()
Fix leak in ci.tableMap.
Removed extra returns in pushdown_init to avoid crashes.
create_select_handler now detects INSERT..SELECT.
buildConstColFromFilter now uses any kind of filter to supply
relevant columns.
Remove strings used by vtable redo phase.
Make FromSubQuery aware of Pushdown handlers.
Changed debug_walk to work around changed Item framework.
Temporary disabled derived handler and unsupported features checks.
