Added LINEAR HASH/KEY mysql compatibility

[mjonss]

What is changed, added or deleted? (Required)

See pingcap/tidb#38450 where CREATE TABLE ... PARTITION BY LINEAR HASH will now create a non-linear HASH partitioned table instead of a non-partitioned normal table.

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What is the related PR or file link(s)?

• This PR is translated from:
• Other reference link(s): Make LINEAR HASH use a HASH partitioned table, instead of a non-partitioned table tidb#38450

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[ti-chi-bot]

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• Oreoxmt
• qiancai

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[qiancai]

@moyun PTAL

[moyun]

I suggest to describe PARTITION BY LINEAR HASH in a new paragraph and remove from current "unsupported" list.
We can say that it is a compatible one, but just at grammar level and we create a hash partition instead. User's original DDL/DML on a MySQL Linear Hash table can keep in use without modification.

[mjonss]

I suggest to describe PARTITION BY LINEAR HASH in a new paragraph and remove from current "unsupported" list. We can say that it is a compatible one, but just at grammar level and we create a hash partition instead. User's original DDL/DML on a MySQL Linear Hash table can keep in use without modification.

OK, so a new paragraph in the partitioned-table.md describing how LINEAR HASH is handled (i.e. like non-linear HASH) and only mention LINEAR KEY in the mysql-compatibility.md ?

[qiancai]

@moyun Would you please help review the latest updates of this PR? Thanks.

[moyun]

LGTM

[Oreoxmt]

LGTM

[Oreoxmt]

Rest LGTM

[qiancai]

/merge

[ti-chi-bot]

This pull request has been accepted and is ready to merge.

Commit hash: a78b4fb

[ti-chi-bot]

In response to a cherrypick label: new pull request created: #11340.