Add list support to vindex functions

[mattlord]

Description

This adds support for vindex function batch lookups using the IN SQL operator:

mysql> select * from customer.hash where id = 100;
+------+-------------+-------------+-----------+------------------+-------+
| id   | keyspace_id | range_start | range_end | hex_keyspace_id  | shard |
+------+-------------+-------------+-----------+------------------+-------+
| 100  | ���V��    | �           |           | 83aab1569cbe1b08 | 80-   |
+------+-------------+-------------+-----------+------------------+-------+
1 row in set (0.00 sec)

mysql> select * from customer.hash where id in (100,1,999);
+------+-------------+-------------+-----------+------------------+-------+
| id   | keyspace_id | range_start | range_end | hex_keyspace_id  | shard |
+------+-------------+-------------+-----------+------------------+-------+
| 100  | ���V��    | �           |           | 83aab1569cbe1b08 | 80-   |
| 1    | k@�J�K�    |             | �         | 166b40b44aba4bd6 | -80   |
| 999  | X���IH    |             | �         | 58afce9fbfe54948 | -80   |
+------+-------------+-------------+-----------+------------------+-------+
3 rows in set (0.00 sec)

mysql> select * from customer.hash where id like "5";
ERROR 1105 (HY000): unsupported: where clause for vindex function must be of the form id = <val> or id in(<val>,...) (not equality)

For more info about the use case, please see: #9042

Related Issue(s)

Fixes: #9042

Checklist

• Should this PR be backported? I don't think so
• Tests were added
• Documentation is not required -- I could not find any documentation to modify for using the vindex functions???

Deployment Notes

[harshit-gangal]

Maybe we can stop calling them unsupported, some of them do not seem reasonable queries.

[harshit-gangal]

We can do it in different PR as well.

[mattlord]

I'm not sure what you mean here. We should call some of them invalid?

[mattlord]

Thanks for the good suggestions, @harshit-gangal ! I've addressed those here: 5af2d18