MDEV-14231 MATCH() AGAINST( IN BOOLEAN MODE), results mismatch

[Thirunarayanan]

• The Jira issue number for this PR is: MDEV-14231

Description

This patch is taken mysql-5.7.
st_mysql_ftparser_boolean_info(): Add variable position to store the correct offset for the default fts parser.
Added plugin_debug.test, multiple_index.test from mysql-5.7

How can this PR be tested?

./mtr innodb_fts.plugin_debug innodb_fts.multiple_index

Basing the PR against the correct MariaDB version

• This is a new feature and the PR is based against the latest MariaDB development branch.
• This is a bug fix and the PR is based against the earliest maintained branch in which the bug can be reproduced.

PR quality check

• I checked the CODING_STANDARDS.md file and my PR conforms to this where appropriate.
• For any trivial modifications to the PR, I am ok with the reviewer making the changes themselves.

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[vuvova]

First, this absolutely cannot go into 10.4.
Second, adding the support for word positions is a feature, not a bug fix.
Third, what is the bug you're fixing? Where's the "results mismatch" ?

[dr-m]

First, this absolutely cannot go into 10.4. Second, adding the support for word positions is a feature, not a bug fix. Third, what is the bug you're fixing? Where's the "results mismatch" ?

Word positions are something that were added in MySQL 5.7 but not in MariaDB Server 10.2. I think that MDEV-24088 is somewhat related to this. This bug was filed when some MySQL 5.7 test cases were being considered for importing, in MDEV-13626.

Hopefullly @Thirunarayanan can clarify this, basically explain how and why MariaDB is incompatible with MySQL in this area.