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e64084d5a3
Reimplement MDEV-14275 Improving memory utilization for information schema Postpone temp table instantiation until after setup_fields(). Replace all unused (not marked in read_set) columns in an I_S table with CHAR(0). This can drastically reduce the footprint of a MEMORY table (a TABLE_CATALOG alone is 1538 bytes per row). This does not change the engine. If the table was decided to be Aria (because of, say, blobs) then after optimization it'll stay Aria even if all blobs were removed. Note 1: when transforming table structure, share->blob_fields is preserved, otherwise Aria might switch from DYNAMIC to STATIC row format and expect a special field for a deleted mark, which create_tmp_tabe didn't provide. Note 2: optimizer was doing handler::info() (to know the number of rows) before the temp table is populated. That didn't make much sense. Now it's done before the table is even instantiated. Preserve the old behavior and report 0 rows. This reverts |
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| .. | ||
| mysql-test/mtr2 | ||
| _check.c | ||
| _rectest.c | ||
| ChangeLog | ||
| CMakeLists.txt | ||
| ha_heap.cc | ||
| ha_heap.h | ||
| heapdef.h | ||
| hp_block.c | ||
| hp_clear.c | ||
| hp_close.c | ||
| hp_create.c | ||
| hp_delete.c | ||
| hp_extra.c | ||
| hp_hash.c | ||
| hp_info.c | ||
| hp_open.c | ||
| hp_panic.c | ||
| hp_rename.c | ||
| hp_rfirst.c | ||
| hp_rkey.c | ||
| hp_rlast.c | ||
| hp_rnext.c | ||
| hp_rprev.c | ||
| hp_rrnd.c | ||
| hp_rsame.c | ||
| hp_scan.c | ||
| hp_static.c | ||
| hp_test1.c | ||
| hp_test2.c | ||
| hp_update.c | ||
| hp_write.c | ||