Subselect selects only 1st column and does not form from keyword

[webmake]

• Laravel Version: 5.5.*
• PHP Version: 7.1

Description:

How to reach properly subquery select attributes as below and add from properly?

 SELECT attribute, COUNT(*) AS items_count
                FROM (
                    SELECT attribute, attribute2
                    FROM history
                    WHERE attribute IN ('1','2','3')
                    GROUP BY attribute, attribute2
                ) subtable
                GROUP BY attribute

Steps To Reproduce:

        dd(\DB::query()
            ->select('attribute')
            ->selectRaw('COUNT(*) AS items_count')
            ->selectSub(function(Builder $query) use ($values){
                 $query->select(['attribute', 'attribute2'])
                    ->from('history')
                    ->whereIn('attribute', $values)
                    ->groupBy('attribute', 'attribute2');
            }, 'subtable')
            ->groupBy('attribute')
            ->toSql());

gives only with one and first attribute:

select `attribute`, COUNT(*) AS items_count, (select `attribute` from `history` where `attribute` in (?, ?, ?) group by `attribute`, `attribute2`) as `subtable` group by `attribute`

due this code:

    protected function parseSubSelect($query)
    {
        if ($query instanceof self) {
            $query->columns = [$query->columns[0]];

[webmake]

Notable, this can't be replaced by

\DB::select('SELECT attribute, COUNT(*) AS items_count
                FROM (
                    SELECT attribute, attribute2
                    FROM history
                    WHERE attribute IN (?)
                    GROUP BY attribute, attribute2
                ) subtable
                GROUP BY attribute',
            $values
        )

because this returns one result, if (?) will be replaced by (?,?) - then 2results will be returned,and so on, so I am not sure how much values there will be, so expected in OOP style to build query, and get properly bindings by laravel itself, but at some point this does not work(?)

[staudenmeir]

The line was added in #19013. Apparently, the PR didn't consider subqueries in the FROM part.

Laravel only uses the method in QueriesRelationships::withCount() (via selectSub()).

If we move $query->columns = [$query->columns[0]]; from Builder::parseSubSelect() to QueriesRelationships::withCount()? The tests still work.

[webmake]

Yeah, but that PR solves some sort of problems. Once again take a look at bolded query parts, that are not presented using selectSub

SELECT attribute, COUNT(*) AS items_count
FROM (
SELECT attribute , attribute2
FROM history
WHERE attribute IN (?, ?, ?)
GROUP BY attribute, attribute2
) subtable
GROUP BY attribute
I think this is not reachable using that function, so question remains how to reach same functionality without any hacks, such as string fill with lenght of parameters in where clause

[staudenmeir]

Can you please take a look at this @cdstarling?

[ghost]

When I created my pull request I initially tried to solve the problem in the QueriesRelationships to avoid this sort of situation in which I missed a use case for the subquery with multiple selects.

For some reason I couldn't get it to work within the withCount method but I've just tried it and it seems to work fine, so I will make a pull request for that now.

[staudenmeir]

@laurencei Can be closed.