fix: prevent duplicate table name errors

[Seb33300]

Fixes #2871, #880 (maybe all issues with Self Join tag )

This PR fixes the duplicate table name SQL error by adding aliases to joined tables.
It also supports multi levels joins:
Eg:

- article.author.name
- article.category.created_by.name
- article.comments[].user.name

⚠️ This PR includes a BC break

As you can see with the test case I modified, this PR comes with a small BC break.
If a column has defined a custom order by using orderColumn(), the table is now using an alias that will not match with the table name.
A new parameter has been added to the orderColumn() callable to pass the column name with alias.

DataTables::eloquent($model)
    ->orderColumn('relation.name', function ($query, $order, $column) {
        // $column = alias.name of the relation.name column
        $query->orderBy($column, $order);
    });

[Seb33300]

I will check failing test next week

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[Seb33300]

Hi @yajra, PR is now ready for review 🙏

[obyajra]

The changes look good. Will hold off for now and review again in v12 (Laravel 12) release since there is a BC.

Will try to complete the v12 within this or earlier next week.

Thanks!

[yajra]

@Seb33300 can you provide an example of the table aliases generated in this PR? One concern I have is the Oracle limitation that only accepts up to 30 chars for object/table name length.

Initial Laravel 12 support merged on the master branch.

Thanks!

[Seb33300]

@yajra It concatenates all parent relation names to create a unique alias name:

updated_by.name => _updated_by.name
created_by.company.name => _created_by_company.name

Here is an example of query generated (on MySQL):

select `users`.* 
from `users` 
left join `users` as `_updated_by` on `users`.`updated_user_id` = `_updated_by`.`id` 
where `_updated_by`.`name` LIKE '%%seb%%' 
order by `_updated_by`.`name` asc 
limit 10 
offset 0

[Seb33300]

One concern I have is the Oracle limitation that only accepts up to 30 chars for object/table name length.

Please note that starting Oracle Database 12c Release 2 (12.2) released in 2017, the maximum size is now 128 chars.
https://oracle-base.com/articles/12c/long-identifiers-12cr2

And all Oracle versions prior that one are already no longer supported by Oracle:
https://en.wikipedia.org/wiki/Oracle_Database

[yajra]

One concern I have is the Oracle limitation that only accepts up to 30 chars for object/table name length.

Please note that starting Oracle Database 12c Release 2 (12.2) released in 2017, the maximum size is now 128 chars. https://oracle-base.com/articles/12c/long-identifiers-12cr2

And all Oracle versions prior that one are already no longer supported by Oracle: https://en.wikipedia.org/wiki/Oracle_Database

Yes, unfortunately - I still have projects that uses old Oracle version >.<

[Seb33300]

Unless you have columns with multiple joins, It's unlikely to happen, but still theoretically possible.

A workaround I can suggest is to use md5 to generate a hash of the alias in case it's more than 30 chars.

[yajra]

Thanks and will review first on an actual project. I just recalled that we rarely use relation and opt to use join statements for more stable results.

[yajra]

Tested on a new Laravel 12 app and works as expected. Tested self-join SQL and seems to be fixed:

SQL Generated:

select * from "users" left join "users" as "_creator" on "users"."created_by" = "_creator"."id" order by "_creator"."name" desc limit 10 offset 0

Is the _ on alias (_creator) intended?

[Seb33300]

Is the _ on alias (_creator) intended?

Yes, this is to prevent a potential conflict with a table name if the relation name is the same as the table name.

[yajra]

Thanks for the feedback. Released on v12 🚀