Column alias might fail in the ORDER BY's subquery clause.

[winoros]

Bug Report

Please answer these questions before submitting your issue. Thanks!

1. Minimal reproduce step (Required)

DROP TABLE IF EXISTS t1, t2;
CREATE TABLE t1 (a INT, b INT);
CREATE TABLE t2 (a INT, b INT);
INSERT INTO t1 VALUES (1, 1);
INSERT INTO t2 VALUES (1, 1);

SELECT one.a, one.b as b2 FROM t1 one ORDER BY (SELECT two.b FROM t2 two WHERE two.a = b2);

2. What did you expect to see? (Required)

The query was executed successfully.

3. What did you see instead (Required)

Error reported that column b2 in the ORDER BY clause is not found.

4. What is your TiDB version? (Required)

current master

[winoros]

Note that SELECT one.a, one.b as b2 FROM t1 one ORDER BY (SELECT two.b FROM t2 two WHERE two.a = one.b2) is ok to report error the one.b2 is not found.

[winoros]

This problem will still exist after #45003 is merged.
It's in the same scope with #42732