NotificationsYou must be signed in to change notification settings
Fork5
Star26

Commit0140a11

committed

Fix thinko in new match_join_clauses_to_index() logic.

We don't need to constrain the other side of an indexable join clause tonot be below an outer join; an example here isSELECT FROM t1 LEFT JOIN t2 ON t1.a = t2.b LEFT JOIN t3 ON t2.c = t3.d;We can consider an inner indexscan on t3.d using c = d as indexqual, eventhough t2.c is potentially nulled by a previous outer join. The comparablelogic in orindxpath.c has always worked that way, but I was being overlycautious here.

1 parent973e9fb commit0140a11Copy full SHA for 0140a11

File tree

1 file changed

-4

lines changed

src/backend/optimizer/path
- indxpath.c

1 file changed

-4

lines changed

`‎src/backend/optimizer/path/indxpath.c`

Lines changed: 4 additions & 4 deletions

Original file line number	Diff line number	Diff line change
`@@ -1702,17 +1702,17 @@ match_join_clauses_to_index(PlannerInfo *root,`
`1702`	`1702`	`* outer join rules.`
`1703`	`1703`	`*`
`1704`	`1704`	`* Instead of considering required_relids, we ignore clauses for which`
`1705`		`- *any referenced rel is in nullable_relids; that means there's an`
`1706`		`- *outerjoin below the clause and so it can't be checked at the`
`1707`		`- *relationscan level.`
	`1705`	`+ *the indexed rel is in nullable_relids; that means there's an outer`
	`1706`	`+ * join below the clause and so it can't be checked at the relation`
	`1707`	`+ * scan level.`
`1708`	`1708`	`*`
`1709`	`1709`	`* Note: unlike create_or_index_quals(), we can accept clauses that`
`1710`	`1710`	`* are marked !is_pushed_down (ie they are themselves outer-join`
`1711`	`1711`	`* clauses). This is OK because any path generated with these clauses`
`1712`	`1712`	`* could only be used in the inside of a nestloop join, which will be`
`1713`	`1713`	`* the nullable side.`
`1714`	`1714`	`*/`
`1715`		`-if (bms_overlap(rinfo->clause_relids,rinfo->nullable_relids))`
	`1715`	`+if (bms_overlap(rel->relids,rinfo->nullable_relids))`
`1716`	`1716`	`continue;`
`1717`	`1717`
`1718`	`1718`	`/* Potentially usable, so see if it matches the index or is an OR */`

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!

Commit0140a11

File tree

1 file changed

1 file changed

`‎src/backend/optimizer/path/indxpath.c`

0 commit comments