P0-[4.0 bug hunting]-[SQL Plan Management]-Value in generated column depends on a WHERE clause

[mrigger]

Consider the following statements:

CREATE TABLE t0(c0 INT AS (c1) UNIQUE, c1 TEXT);
INSERT INTO t0(c1) VALUES (0.5);
SELECT t0.c0 FROM t0 WHERE t0.c1 + 0.5; -- expected: {1}, actual: {0} 

Unexpectedly, the SELECT fetches an attribute value of 0, rather than 1. When removing the WHERE clause, the query works as expected:

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mysql> CREATE TABLE t0(c0 INT AS (c1) UNIQUE, c1 TEXT);
Query OK, 0 rows affected (0.00 sec)

mysql> INSERT INTO t0(c1) VALUES (0.5);
Query OK, 1 row affected (0.00 sec)

mysql> SELECT t0.c0 FROM t0 WHERE t0.c1 + 0.5; -- expected: {1}, actual: {0} 
+------+
| c0   |
+------+
|    0 |
+------+
1 row in set, 1 warning (0.00 sec)

mysql> SELECT t0.c0 FROM t0;
+------+
| c0   |
+------+
|    1 |
+------+
1 row in set (0.00 sec)

I found this based on the latest master commit 187f225002b67daa47992816f6ef5ddb76b0f68a, and also checked that this reproduces on the 4.0 RC. On the latest master commit, the addition + 0.5 is not necessary to reproduce this.

[shuke987]

/bug P1