Support fast_analyze_table variable, introduced in public MySQL fork

[shlomi-noach]

Description

This PR follows up on #13352. It utilizes fast_analyze_table (global/session variable), introduced in planetscale/mysql-server@c8a9d93 as part of https://github.com/planetscale/mysql-server/releases/tag/8.0.34-ps1.

In this PR, and when --analyze-table DDL strategy flag is provided, the Online DDL executor checks for existence of this variable. If the variable exists, then the executor will set it to 1 prior to running ANALYZE TABLE ....

This introduced code is safe to run on MySQL versions that do not support the variable, as the initial probing query is

show global variables like 'fast_analyze_table'

which is always safe to run. The query returns 0 rows on unsupporting servers.

With fast_analyze_table, an ANALYZE TABLE only updates stats for the clustering index (normally the PRIMARY KEY).

Related Issue(s)

• Feature Request: improved Online DDL row estimation  #13437
• Online DDL: improved row estimation via ANALYE TABLE with --analyze-table strategy flag #13352

Checklist

• "Backport to:" labels have been added if this change should be back-ported
• Tests were added or are not required
• Did the new or modified tests pass consistently locally and on the CI
• Documentation was added or is not required

Deployment Notes

[vitess-bot]

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