MDEV-40168 wip

[mariadb-YuchenPei]

TODOs on top of those in the patch diff:

• EXPLAIN output should not say fulltext
• check type match to avoid false negative / positive bugs in mysql
• transcode the value into the index charset in mvi_encode_key

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[spetrunia]

So, the index is now shown in SHOW CREATE TABLE ?

[spetrunia]

rather is NOT shown in SHOW CREATE TABLE

[spetrunia]

For the record: index is not visible in information_schema:

create table t25 (
  js json,
  key idx ((CAST(json_extract(js, '$.tags') AS CHAR(6) ARRAY)))
)engine=innodb;
select * from information_schema.statistics where table_name='t25'

gives nothing.

[spetrunia]

And this crashes:

create table t25 (
  js json,
  key idx ((CAST(json_extract(js, '$.tags') AS CHAR(6) ARRAY)))
)engine=innodb;
insert into t25 values ('{}');

[mariadb-YuchenPei]

For the record: index is not visible in information_schema:

create table t25 (
  js json,
  key idx ((CAST(json_extract(js, '$.tags') AS CHAR(6) ARRAY)))
)engine=innodb;
select * from information_schema.statistics where table_name='t25'

gives nothing.

Isn't this the same problem as your other comment #5620 (comment)?

[mariadb-YuchenPei]

And this crashes:

create table t25 (
  js json,
  key idx ((CAST(json_extract(js, '$.tags') AS CHAR(6) ARRAY)))
)engine=innodb;
insert into t25 values ('{}');

Fixed now