NotificationsYou must be signed in to change notification settings
Fork6
Star31

Commit3f1356e

committed

Fix handling of NULLs when merging BRIN summaries

When merging BRIN summaries, union_tuples() did not correctly update thetarget hasnulls/allnulls flags. When merging all-NULL summary into asummary without any NULL values, the result had both flags set to false(instead of having hasnulls=true).This happened because the code only considered the hasnulls flags,ignoring the possibility the source summary has allnulls=true.Discovered while investigating issues with handling empty BRIN rangesand handling of NULL values, but it's a separate problem (has nothing todo with empty ranges).Fixed by considering both flags on the source summary, and updating thehasnulls flag on the target summary.Backpatch to 11. The bug exists since 9.5 (where BRIN indexes wereintroduced), but those releases are EOL already.Discussion:https://postgr.es/m/9d993d0d-e431-2196-9ccc-0554d0e60154%40enterprisedb.com

1 parentccd3623 commit3f1356eCopy full SHA for 3f1356e

File tree

1 file changed

-1

lines changed

src/backend/access/brin
- brin.c

1 file changed

-1

lines changed

`‎src/backend/access/brin/brin.c`

Lines changed: 9 additions & 1 deletion

Original file line number	Diff line number	Diff line change
`@@ -1623,8 +1623,11 @@ union_tuples(BrinDesc bdesc, BrinMemTuple a, BrinTuple *b)`
`1623`	`1623`
`1624`	`1624`	`if (opcinfo->oi_regular_nulls)`
`1625`	`1625`	`{`
	`1626`	`+/* Does the "b" summary represent any NULL values? */`
	`1627`	`+boolb_has_nulls= (col_b->bv_hasnulls\|\|col_b->bv_allnulls);`
	`1628`	`+`
`1626`	`1629`	`/* Adjust "hasnulls". */`
`1627`		`-if (!col_a->bv_hasnulls&&col_b->bv_hasnulls)`
	`1630`	`+if (!col_a->bv_allnulls&&b_has_nulls)`
`1628`	`1631`	`col_a->bv_hasnulls= true;`
`1629`	`1632`
`1630`	`1633`	`/* If there are no values in B, there's nothing left to do. */`
`@@ -1636,12 +1639,17 @@ union_tuples(BrinDesc bdesc, BrinMemTuple a, BrinTuple *b)`
`1636`	`1639`	`* values from B into A, and we're done. We cannot run the`
`1637`	`1640`	`* operators in this case, because values in A might contain`
`1638`	`1641`	`* garbage. Note we already established that B contains values.`
	`1642`	`+ *`
	`1643`	`+ * Also adjust "hasnulls" in order not to forget the summary`
	`1644`	`+ * represents NULL values. This is not redundant with the earlier`
	`1645`	`+ * update, because that only happens when allnulls=false.`
`1639`	`1646`	`*/`
`1640`	`1647`	`if (col_a->bv_allnulls)`
`1641`	`1648`	`{`
`1642`	`1649`	`inti;`
`1643`	`1650`
`1644`	`1651`	`col_a->bv_allnulls= false;`
	`1652`	`+col_a->bv_hasnulls= true;`
`1645`	`1653`
`1646`	`1654`	`for (i=0;i<opcinfo->oi_nstored;i++)`
`1647`	`1655`	`col_a->bv_values[i]=`

0 commit comments

Comments

(0)

Movatterモバイル変換

Navigation Menu

Search code, repositories, users, issues, pull requests...

Provide feedback

Saved searches

Use saved searches to filter your results more quickly

Uh oh!

Commit3f1356e

File tree

1 file changed

1 file changed

`‎src/backend/access/brin/brin.c`

0 commit comments