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This task is to allow storage engines that can execute GROUP BY or summary queries efficiently to intercept a full query or sub query from MariaDB and deliver the result either to the client or to a temporary table for further processing. - Added code in sql_select.cc to intercept GROUP BY queries. Creation of group_by_handler is done after all optimizations to allow storage engine to benefit of an optimized WHERE clause and suggested indexes to use. - Added group by handler to sequence engine and a group_by test suite as a way to test the new interface. - Intercept EXPLAIN with a message "Storage engine handles GROUP BY" libmysqld/CMakeLists.txt: Added new group_by_handler files sql/CMakeLists.txt: Added new group_by_handler files sql/group_by_handler.cc: Implementation of group_by_handler functions sql/group_by_handler.h: Definition of group_by_handler class sql/handler.h: Added handlerton function to create a group_by_handler, if the storage engine can intercept the query. sql/item_cmpfunc.cc: Allow one to evaluate item_equal any time. sql/sql_select.cc: Added code to intercept GROUP BY queries - If all tables are from the same storage engine and the query is using sum functions, call create_group_by() to check if the storage engine can intercept the query. - If yes: - create a temporary table to hold a GROUP_BY row or result - In do_select() intercept normal query execution by instead calling the group_by_handler to get the result - Intercept EXPLAIN sql/sql_select.h: Added handling of group_by_handler Added caching of the original join tab (needed for cleanup after group_by handler) storage/sequence/mysql-test/sequence/group_by.result: Test group_by_handler interface storage/sequence/mysql-test/sequence/group_by.test: Test group_by_handler interface storage/sequence/sequence.cc: Added simple group_by_engine for handling COUNT(*) and SUM(primary_key). This was done as a test of the group_by_handler interface |
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.. | ||
examples | ||
CMakeLists.txt | ||
emb_qcache.cc | ||
emb_qcache.h | ||
embedded_priv.h | ||
lib_sql.cc | ||
libmysqld.c | ||
libmysqld.def | ||
libmysqld.rc | ||
resource.h |