*: fix updating the column value when the column is dropping and in WriteOnly state (#15539)

[sre-bot]

cherry-pick #15539 to release-3.0
conflicts:

• ddl/db_change_test.go
• executor/update.go
• planner/core/logical_plan_builder.go

Some variables and functions in v4.0 are not in v3.0, I hope that reviewers will be more careful

---

---

What problem does this PR solve?

Issue Number: close #15386

create table t (a int, b int)
insert into t values(1,1);

Do the following:

time	connection1	connection2
t1	drop column
t2	column state (write only)	update t set a =5 ,b=2
t3	column state (write only)	update t set a=10 where b=2
t4	column state (none)	select * from t

The result:

tidb> select * from t;
+------+
| a |
+------+
| 5 |
+------+
1 row in set (0.00 sec)

Problem Summary:
When the column is dropping and in WriteOnly state, the value of this column cannot be explicitly updated.

What is changed and how it works?

What's Changed:
When the column is in a falling state and in WriteOnly state, if we update this column value explicitly, an error will be returned.

Related changes

• Need to cherry-pick to the release branch

Check List

Tests

• Unit test

Side effects

• Performance regression
  • Consumes more CPU
  • Consumes more MEM
• Breaking backward compatibility

Release note

[sre-bot]

/run-all-tests

[zimulala]

Some variables and functions in v4.0 are not in v3.0, I hope that reviewers will be more careful

[zimulala]

PTAL @crazycs520 @tangenta @AilinKid

[tangenta]

Panic?

[bb7133]

Please add error for getTableOffset.

[zimulala]

Done

[zimulala]

PTAL @tangenta @bb7133

[AilinKid]

LGTM

[zz-jason]

LGTM

[sre-bot]

Your auto merge job has been accepted, waiting for 15356

[sre-bot]

/run-all-tests