ddl: fix the issue about create columns with wrong default when sql_mode is empty.

[zimulala]

What problem does this PR solve?

Issue Number: close https://github.com/pingcap/tidb/issues/52972, close https://github.com/pingcap/tidb/issues/51320

Problem Summary: Case1:

set @@sql_mode='STRICT_TRANS_TABLES';
drop table if exists t1;
create table t1(a int);
insert into t1 values(1);
alter table t1 add column(b tinyint default '11111111');

Case2:

set @@sql_mode='';
drop table if exists t1;
create table t1(a int);
insert into t1 values(1);
alter table t1 add column(b tinyint default '11111111');

Now the TiDB behaviors:

• When the @@sql_mode is STRICT_TRANS_TABLES(Case1) the result is Invalid default value for 'b'.
• When the @@sql_mode is ''(Case2) the result is successful.

Now the MySQL(MySQL 5.7.44 and 8.0.18 MySQL) behaviors:

• In Both cases the result is Invalid default value for 'b'.

What changed and how does it work?

Check List

Tests

• [x] Unit test
• [ ] Integration test
• [ ] Manual test (add detailed scripts or steps below)
• [ ] No need to test

  • [ ] I checked and no code files have been changed.

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

[tiprow[bot]]

Hi @zimulala. Thanks for your PR.

PRs from untrusted users cannot be marked as trusted with /ok-to-test in this repo meaning untrusted PR authors can never trigger tests themselves. Collaborators can still trigger tests on the PR using /test all.

I understand the commands that are listed here.

Instructions for interacting with me using PR comments are available [here](https://git.k8s.io/community/contributors/guide/pull-requests.md). If you have questions or suggestions related to my behavior, please file an issue against the [kubernetes/test-infra](https://github.com/kubernetes/test-infra/issues/new?title=Prow%20issue:) repository.

[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 55.7545%. Comparing base (1d698c7) to head (800b0b0). Report is 12 commits behind head on master.

Additional details and impacted files

```diff @@ Coverage Diff @@ ## master #52988 +/- ## ================================================= - Coverage 72.3811% 55.7545% -16.6266% ================================================= Files 1482 1597 +115 Lines 428743 600172 +171429 ================================================= + Hits 310329 334623 +24294 - Misses 99115 242466 +143351 - Partials 19299 23083 +3784 ``` | [Flag](https://app.codecov.io/gh/pingcap/tidb/pull/52988/flags?src=pr&el=flags&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=pingcap) | Coverage Δ | | |---|---|---| | [integration](https://app.codecov.io/gh/pingcap/tidb/pull/52988/flags?src=pr&el=flag&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=pingcap) | `37.1662% <85.7142%> (?)` | | | [unit](https://app.codecov.io/gh/pingcap/tidb/pull/52988/flags?src=pr&el=flag&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=pingcap) | `71.2434% <100.0000%> (+0.0249%)` | :arrow_up: | Flags with carried forward coverage won't be shown. [Click here](https://docs.codecov.io/docs/carryforward-flags?utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=pingcap#carryforward-flags-in-the-pull-request-comment) to find out more. | [Components](https://app.codecov.io/gh/pingcap/tidb/pull/52988/components?src=pr&el=components&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=pingcap) | Coverage Δ | | |---|---|---| | [dumpling](https://app.codecov.io/gh/pingcap/tidb/pull/52988/components?src=pr&el=component&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=pingcap) | `53.9957% <ø> (ø)` | | | [parser](https://app.codecov.io/gh/pingcap/tidb/pull/52988/components?src=pr&el=component&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=pingcap) | `∅ <ø> (∅)` | | | [br](https://app.codecov.io/gh/pingcap/tidb/pull/52988/components?src=pr&el=component&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=pingcap) | `49.2175% <ø> (+8.0736%)` | :arrow_up: |

[zimulala]

/retest

[tiprow[bot]]

@zimulala: Cannot trigger testing until a trusted user reviews the PR and leaves an /ok-to-test message.

In response to [this](https://github.com/pingcap/tidb/pull/52988#issuecomment-2084224153): >/retest Instructions for interacting with me using PR comments are available [here](https://git.k8s.io/community/contributors/guide/pull-requests.md). If you have questions or suggestions related to my behavior, please file an issue against the [kubernetes/test-infra](https://github.com/kubernetes/test-infra/issues/new?title=Prow%20issue:) repository.

[ti-chi-bot[bot]]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: Defined2014, tangenta

The full list of commands accepted by this bot can be found here.

The pull request process is described here

Needs approval from an approver in each of these files: - ~~[OWNERS](https://github.com/pingcap/tidb/blob/master/OWNERS)~~ [Defined2014,tangenta] - ~~[pkg/ddl/OWNERS](https://github.com/pingcap/tidb/blob/master/pkg/ddl/OWNERS)~~ [tangenta] Approvers can indicate their approval by writing `/approve` in a comment Approvers can cancel approval by writing `/approve cancel` in a comment

[ti-chi-bot[bot]]

[LGTM Timeline notifier]

Timeline:

• 2024-04-30 02:37:33.103366475 +0000 UTC m=+324806.860502042: :ballot_box_with_check: agreed by Defined2014.
• 2024-04-30 06:26:19.64581038 +0000 UTC m=+338533.402945950: :ballot_box_with_check: agreed by tangenta.

[ti-chi-bot]

In response to a cherrypick label: new pull request created to branch release-8.1: #53002.