Opened 9 months ago

Closed 9 months ago

Last modified 9 months ago

#35156 closed Cleanup/optimization (fixed)

Update Doc comment about SQLite foreign keys

Reported by: bcail Owned by: bcail
Component: Documentation Version: dev
Severity: Normal Keywords:
Cc: bcail Triage Stage: Ready for checkin
Has patch: yes Needs documentation: no
Needs tests: no Patch needs improvement: no
Easy pickings: no UI/UX: no

Description

Multi-database docs say the following:

However, if you’re using SQLite or MySQL with MyISAM tables, there is no enforced referential integrity; as a result, you may be able to ‘fake’ cross database foreign keys.

But, foreign keys are enforced at the database level in SQLite, because the PRAGMA is turned on.

Should this comment be updated?

Change History (8)

comment:1 by Baptiste Mispelon, 9 months ago

Triage Stage: UnreviewedAccepted

Hi,

It seems you might be correct. The paragraph of documentation you linked to was introduced 14 years ago with #13316, whereas FK constraint were turned on in sqlite only 7 years ago with #14204 (I found that using the "blame" feature on github).

So we should fix this, but that leaves me with two questions:

1) Is the comment about MyISAM tables still correct then?
2) Are there other places in the documentation that could be incorrect with regards to sqlite and FK constraints?

in reply to:  1 comment:2 by Mariusz Felisiak, 9 months ago

Replying to Baptiste Mispelon:

1) Is the comment about MyISAM tables still correct then?

Yes, it is https://dev.mysql.com/doc/refman/8.3/en/ansi-diff-foreign-keys.html:

"For storage engines that do not support foreign keys (such as MyISAM),..."

comment:3 by bcail, 9 months ago

2) Are there other places in the documentation that could be incorrect with regards to sqlite and FK constraints?

I just looked and didn't find any.

comment:4 by bcail, 9 months ago

Owner: changed from nobody to bcail
Status: newassigned

I can open a PR.

comment:5 by bcail, 9 months ago

Has patch: set

comment:6 by Mariusz Felisiak, 9 months ago

Triage Stage: AcceptedReady for checkin
Type: UncategorizedCleanup/optimization

comment:7 by Mariusz Felisiak <felisiak.mariusz@…>, 9 months ago

Resolution: fixed
Status: assignedclosed

In b3dc8068:

Fixed #35156 -- Removed outdated note about not supporting foreign keys by SQLite.

comment:8 by Mariusz Felisiak <felisiak.mariusz@…>, 9 months ago

In d28c61b:

[5.0.x] Fixed #35156 -- Removed outdated note about not supporting foreign keys by SQLite.

Backport of b3dc80682e678b20c89fb2a430c0bc77960a29ac from main

Note: See TracTickets for help on using tickets.
Back to Top