This is expected behavior. You need to remove:

$elementos->select('reclamacion.*')->distinct();

Yeah, if one wants the sum ofall one shouldn't use distinct—why would one anyway in such a case?

You can set distinct to false and after sum reset it to the initial value.

I need DISTINCT because the original query has many joins, and the query selects many fields.

Thedistinct option should apply to the query itself, but it shouldn't affect theSUM function of that query at all.

The sum function should only perform the sum of the amounts from the result of the original query, not recalculate the records of that query.

If you run a SQL SUM query, it doesn't group by amounts, but by all fields in the query, so in this case it would leave all records.

You can set distinct to false and after sum reset it to the initial value.

In that case, there would be more results than I need, because of the joins.

This probably isn't a Laravel but an SQL issue. Could you run->ddRawSql() on the query and share the result with us?

->ddRawSql()

This is the result of ddRawSql()

select
sum(distinct IFNULL(iva), 0)
)
) as aggregate
from
reclamacion
where
reclamacion.deleted_at is null
andreclamacion.reclamar_a = Instalador
andreclamacion.asignado_empresa in (615, 908, 909)

@DavidVaras ddRawSql explains the behavior.
When you call->distinct() on Laravel's query builder, it will be just set on the builder. When you then call->sum(), Laravel's aggregate method generatesSUM(DISTINCT column) as ddRawSql shows.

This is intentional in Laravel.

What you want:SELECT DISTINCT * FROM table then sum
What Laravel does:SELECT SUM(DISTINCT column) which will be sum unique values only

Solution can be what@macropay-solutions mentioned or more readable version which shows what you want first then what you want next.

@DavidVaras ddRawSql explains the behavior. When you call->distinct() on Laravel's query builder, it will be just set on the builder. When you then call->sum(), Laravel's aggregate method generatesSUM(DISTINCT column) as ddRawSql shows.

This is intentional in Laravel.

What you want:SELECT DISTINCT * FROM table then sum What Laravel does:SELECT SUM(DISTINCT column) which will be sum unique values only

Solution can be what@macropay-solutions mentioned or more readable version which shows what you want first then what you want next.

If you useget() to sum the amounts in the rows, the result is different than if you use theSUM() function on the same query.

In my humble opinion, you should never useDISTINCT to calculate the total in a sum; it doesn't make sense that if two rows have the same value they aren't summed, much less that this is a generalized calculation method for all the rows in a query.

For the calculation, I'm simply using a foreach loop in PHP.

This ensures that the totaled values ​​match the values ​​returned by the query and those displayed on the screen.

@DavidVaras,
You are right, but I think it is better to play with Laravel queries like this by using both get and sum, or any others which provide the expected result:

$total = Model::distinct()    ->get(['column'])    ->sum('column');

Using PHP on the large data, will cause less efficient to loads all rows into memory.

Okay, thank you all very much. I thought that was how it was supposed to work.