Fix count helper function for self-referencing relations

[hanneskuettner]

Scope

With a self referencing collection (e.g. node with the related field parent and children), when to filter it with the count(*) function the following query was generated:

select * from `node` where ((select count(*) from `node` where `parent` = `node`.`id`) > ?) limit ?

The inner where clause mistakingly references the inner table node for comparison, instead of the outer node table.

This PR fixes this by always aliasing the table in the inner where generated by the _relationalCount helper:

select * from `node` where ((select count(*) from `node` as `pizml` where `pizml`.`parent` = `node`.`id`) > ?) limit ?

What's changed:

• Introduce table alias in _relationalCount helper method

Potential Risks / Drawbacks

• None? This change should only introduce an alias that is redundant in the best case, and necessary in the other cases.

Review Notes / Questions

• Since blackbox tests aren't really a thing right now for different DB vendors I have tested this change on
  • SQLite ✅
  • Postgres ✅
  • MySQL ✅
  • MariaDB ✅
  • CockroachDB ✅
  • MSSQL ❓
  • Oracle ❓
  • Redshift ❓

---

Fixes #14338

[changeset-bot]

🦋 Changeset detected

Latest commit: 55c60b6

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 2 packages

Name	Type
@directus/api	Patch
directus	Patch

Not sure what this means? Click here to learn what changesets are.

Click here if you're a maintainer who wants to add another changeset to this PR

[paescuj]

Nice fix!