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| author | sergefp@mysql.com <> | 2004-05-13 01:38:40 +0400 |
|---|---|---|
| committer | sergefp@mysql.com <> | 2004-05-13 01:38:40 +0400 |
| commit | a46d7542c94eb5848231324a043ddccffbc552b0 (patch) | |
| tree | 34118ff1da06b90ade9507174ddccf92c228286a /include/my_base.h | |
| parent | b2efad935b38bfcf8177837082e3946c60ba8328 (diff) | |
| download | mariadb-git-a46d7542c94eb5848231324a043ddccffbc552b0.tar.gz | |
This is first cset for WL#1394 "Optimize index merge when all involved index ranges include only values with equal keys"
The main idea is to exploit the fact that key scans for "key=const" return ordered sequences of rowids.
Diffstat (limited to 'include/my_base.h')
| -rw-r--r-- | include/my_base.h | 8 |
1 files changed, 7 insertions, 1 deletions
diff --git a/include/my_base.h b/include/my_base.h index 89b46de520f..19843d413c4 100644 --- a/include/my_base.h +++ b/include/my_base.h @@ -132,7 +132,13 @@ enum ha_extra_function { HA_EXTRA_RETRIEVE_ALL_COLS, HA_EXTRA_PREPARE_FOR_DELETE, HA_EXTRA_PREPARE_FOR_UPDATE, /* Remove read cache if problems */ - HA_EXTRA_PRELOAD_BUFFER_SIZE /* Set buffer size for preloading */ + HA_EXTRA_PRELOAD_BUFFER_SIZE, /* Set buffer size for preloading */ + /* + When using HA_EXTRA_KEYREAD, overwrite only key member fields and keep + other fields intact. When this is off (by default) InnoDB will use memcpy + to overwrite entire row. + */ + HA_EXTRA_KEYREAD_PRESERVE_FIELDS }; /* The following is parameter to ha_panic() */ |