planner: fix dropping non-ScalarFunction when extractCol for memtable (#40935)

[ti-chi-bot]

This is an automated cherry-pick of #40935

Signed-off-by: Zhenchi zhongzc_arch@outlook.com

Issue Number: close #40937

Problem Summary:

We can see extractLikePatternCol and extractTimeRange will keep non-ScalarFunctions by appending them to remained.

tidb/planner/core/memtable_predicate_extractor.go

Lines 432 to 437 in d6302c1

	for _, expr := range predicates {
	fn, ok := expr.(*expression.ScalarFunction)
	if !ok {
	remained = append(remained, expr)
	continue
	}

tidb/planner/core/memtable_predicate_extractor.go

Lines 265 to 270 in d6302c1

	for _, expr := range predicates {
	fn, ok := expr.(*expression.ScalarFunction)
	if !ok {
	remained = append(remained, expr)
	continue
	}

But not for extractCol. It seems a bug.

tidb/planner/core/memtable_predicate_extractor.go

Lines 210 to 214 in d6302c1

	for _, expr := range predicates {
	fn, ok := expr.(*expression.ScalarFunction)
	if !ok {
	continue
	}

What is changed and how it works?

Keep them the same.

Before this patch:

mysql root@127.0.0.1:information_schema> explain select * from `CLUSTER_HARDWARE` where `TYPE`;
+----------------+----------+------+------------------------+---------------+
| id             | estRows  | task | access object          | operator info |
+----------------+----------+------+------------------------+---------------+
| MemTableScan_5 | 10000.00 | root | table:CLUSTER_HARDWARE |               |
+----------------+----------+------+------------------------+---------------+

With this patch:

mysql root@127.0.0.1:information_schema> explain select * from `CLUSTER_HARDWARE` where `TYPE`;
+------------------+----------+------+------------------------+---------------+
| id               | estRows  | task | access object          | operator info |
+------------------+----------+------+------------------------+---------------+
| Selection_5      | 8000.00  | root |                        | Column#1      |
| └─MemTableScan_6 | 10000.00 | root | table:CLUSTER_HARDWARE |               |
+------------------+----------+------+------------------------+---------------+

Check List

Tests

• Unit test
• Integration test
• Manual test (add detailed scripts or steps below)
• No code

Side effects

• Performance regression: Consumes more CPU
• Performance regression: Consumes more Memory
• Breaking backward compatibility

Documentation

• Affects user behaviors
• Contains syntax changes
• Contains variable changes
• Contains experimental features
• Changes MySQL compatibility

Release note

Please refer to Release Notes Language Style Guide to write a quality release note.

None

[ti-chi-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: hawkingrei, qw4990

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[ti-chi-bot]

[LGTM Timeline notifier]

Timeline:

• 2024-02-20 07:34:42.370872678 +0000 UTC m=+342571.118495783: ☑️ agreed by hawkingrei.
• 2024-02-20 07:37:22.76302882 +0000 UTC m=+342731.510651932: ☑️ agreed by qw4990.