Count does not work as expected in Laravel Query Builder - php

Question

I am trying to get how many names do I have in database. For this purpose I am using Query Builder like this:
$namesIdsCount = DB::table('names_to_options')
->select('name_id')
->groupBy('name_id')
->havingRaw($having)
->count();
Is says that 24, which is not correct, because if I will write code like this:
$namesIdsCount = DB::table('names_to_options')
->select('name_id')
->groupBy('name_id')
->havingRaw($having)
->get();
result object contains 247 elements, which is correct. I have tried to play with skip/take, but still no results. Where am I wrong? Thanks for any help.

Answer 1

I think it's the other way around, you're not getting 24 groups. You're getting 24 elements within the first group. That configuration results in the following query:
SELECT
COUNT(*) AS 'aggregate',
`name_id`
FROM `names_to_options`
WHERE EXISTS(
{your $havingRaw sub-query}
)
GROUP BY `name_id`;
What you end up with will look something like this:
+---------------+---------+
| aggregate | name_id |
+---------------+---------+
| 24 | 1 |
+---------------+---------+
| 5 | 2 |
+---------------+---------+
| 30 | 3 |
+---------------+---------+
| ... and so on | 4 |
+---------------+---------+
Query\Builder just doesn't realize you can get more than one result back when count() is involved.
You were pretty close to the right answer yourself though.
$namesIdsCount = DB::table('names_to_options')
->select('name_id')
->groupBy('name_id')
->havingRaw($having)
->get();
get() returns an Eloquent\Collection, child of Support\Collection, which has its own version of the count method. So your answer is just:
$namesIdsCount = DB::table('names_to_options')
->select('name_id')
->groupBy('name_id')
->havingRaw($having)
->get()
->count();
If you really want this to happen in MySQL, the query you want to happen would look like this:
SELECT COUNT(*) FROM (
SELECT
`name_id`
FROM `names_to_options`
WHERE EXISTS(
{your $havingRaw sub-query}
)
GROUP BY `name_id`
) AS temp;
For that, you can do this:
$query = DB::table('names_to_options')
->select('name_id')
->groupBy('name_id')
->havingRaw($having);
$sql = $query->toSql();
$values = $query->getBindings();
$count = DB::table(DB::raw('('.$sql.') AS `temp`'))
->selectRaw("COUNT(*) AS 'aggregate'", $values)
->first()
->aggregate;
MySQL performance can get a little hairy when asking it to write temp-tables like that though, so you'll have to experiment to see which option is faster.

Answer 2

Inuyaki is right
(id, name_id),
(1,1),
(2,1),
(3,2),
(4,3)
There are are four rows so get() method will return 4 rows
but there are three groups if you use groupBy [name_id]
1 (1,1)
2 (2)
3 (3)
now count will return 3
hope this will help.