diff options
| author | drh <drh@noemail.net> | 2020-09-30 18:06:51 +0000 |
|---|---|---|
| committer | drh <drh@noemail.net> | 2020-09-30 18:06:51 +0000 |
| commit | fad4dd0fd1826c08f3f04c81b77d51dcb7f1c661 (patch) | |
| tree | fe455e03ad7c483fe1391b97a002abb9fc60042e /src/expr.c | |
| parent | 395a60dad467819ba520aa528dd4983e908c50ec (diff) | |
| parent | 4f65b3bbfb2205dba20740d0b31c83fbc81f8931 (diff) | |
| download | sqlite-fad4dd0fd1826c08f3f04c81b77d51dcb7f1c661.tar.gz sqlite-fad4dd0fd1826c08f3f04c81b77d51dcb7f1c661.zip | |
Improved query optimization for multi-column indexes where the second or
later columns are constrained by an IN operator and the earlier index columns
limit the search to a small number of rows. Use the new OP_SeekScan opcode
which does scanning of the relevant range of the index but gives up and
falls back to doing a seek if the number of rows scanned grows to large,
in order to guard against pathological cases where the estimated number
of rows to be scanned is far too small.
FossilOrigin-Name: 4a43430fd23f88352c33b29c4c105b72f6dc821f94bf362040c41a1648c402e5
Diffstat (limited to 'src/expr.c')
0 files changed, 0 insertions, 0 deletions