`vtexplain` fails for vindex lookup queries with duplicate / equivalent values.

[arthurschreiber]

Description

If a query contains an IN condition with multiple equivalent values for lookup_unique vindexes, vtexplain fails with:

Lookup.Map: unexpected multiple results from vindex <vindex>

This is due to vtexplain "simulating" that each value of the tuple in a lookup vindex query returns a result row, but when values are equivalent (e.g. 1 and "1"), only a single row should be returned.

I tried to implement this by determining the type of the column being matched against, converting each value of the tuple to that type, and then making sure vtexplain only considers non-duplicate values.

Related Issue(s)

Checklist

• [ ] "Backport me!" label has been added if this change should be backported
• [ ] Tests were added or are not required
• [ ] Documentation was added or is not required

Deployment Notes

[vitess-bot[bot]]

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[vitess-bot[bot]]

I was unable to backport this Pull Request to the following branches: release-14.0.