On 2/3/25 00:57, Alexander Korotkov wrote:
On Thu, Jan 30, 2025 at 3:23 PM Pavel Borisov <pashkin.e...@gmail.com> wrote:
On Tue, 28 Jan 2025 at 12:42, Andrei Lepikhov <lepi...@gmail.com> wrote:
On 1/28/25 11:36, Andrei Lepikhov wrote:
On 1/27/25 16:50, Alexander Korotkov wrote:
qsort(matches, n, sizeof(OrArgIndexMatch), or_arg_index_match_cmp);
To fit an index, the order of elements in the target array of the
`ScalarArrayOpExpr` may change compared to the initial list of OR
expressions. If there are indexes that cover the same set of columns but
in reverse order, this could potentially alter the position of a
Subplan. However, I believe this is a rare case; it is supported by the
initial OR path and should be acceptable.
I beg your pardon - I forgot that we've restricted the feature's scope
and can't combine OR clauses into ScalarArrayOpExpr if the args list
contains references to different columns.
So, my note can't be applied here.
--
regards, Andrei Lepikhov
I've looked at the patch v46-0001
Looks good to me.
There is a test that demonstrates the behavior change. Maybe some more
cases like are also worth adding to a test.
+SELECT * FROM bitmap_split_or t1, bitmap_split_or t2 WHERE t1.a=t2.c
OR (t1.a=t2.b OR t1.a=1);
+ QUERY PLAN
+--------------------------------------------------------
+ Nested Loop
+ -> Seq Scan on bitmap_split_or t2
+ -> Index Scan using t_a_b_idx on bitmap_split_or t1
+ Index Cond: (a = ANY (ARRAY[t2.c, t2.b, 1]))
+(4 rows)
+
+EXPLAIN (COSTS OFF)
+SELECT * FROM bitmap_split_or t1, bitmap_split_or t2 WHERE t1.c=t2.b OR t1.a=1;
+ QUERY PLAN
+----------------------------------------------
+ Nested Loop
+ Join Filter: ((t1.c = t2.b) OR (t1.a = 1))
+ -> Seq Scan on bitmap_split_or t1
+ -> Materialize
+ -> Seq Scan on bitmap_split_or t2
+(5 rows)
+
+EXPLAIN (COSTS OFF)
Added more tests to join.sql
I have made final pass through the changes. All looks good.
Only one thing looks strange for me - multiple '42's in the output of
the test. May be reduce output by an aggregate in the target list of the
query?
--
regards, Andrei Lepikhov
