Re: UNION makes strange duplicates

Tomasz Brzezina <biuro@sam.w3.pl> writes:
> document_id     vat_type_id     vat_type_value     document_netto_value
> 65615        1        0        0
> 65615        4        0.07        -12.5327
> 65615        5        0.22        -7.31148
> 65615        5        0.22        -7.31148

Perhaps document_item_value is float4, and there is some low-order-bit
difference in the sums?

            regards, tom lane