Re: BUG #18774: Not the required output of the query used in the function(delete_from_table1) in postgresql9.4

Hello SIr,
Please clarify about why $1 is not been replaced by 'colname' in
delete_from_table2
function.

regards,

On Wed, Jan 22, 2025 at 10:13 PM David G. Johnston <
david(dot)g(dot)johnston(at)gmail(dot)com> wrote:

> You seem to have reversed which query you deem correct...
>
> On Wed, Jan 22, 2025 at 8:59 AM Rajni Bobal <rajnibobal(at)gmail(dot)com> wrote:
>
>>
>> || quote_ident(colname)
>> || ' IN (SELECT '
>> || quote_ident(colname)
>> || ' FROM '
>> || quote_ident(sel_tblname)
>>
>
> This deletes rows from the table depending upon finding the same value in
> colname in the subquery.
>
>
>> ' where $1 in (select $1 from ' || quote_ident(sel_tblname) ||
>>
>
> This deletes rows from the table depending only upon finding at least one
> row in the subquery - the limit is basically pointless. Since all rows
> return the value provided in $1, and $1 = $1.
>
> So these indeed produce different results, as they should. The "error"
> one is behaving exactly as it should. If it doesn't do what you want -
> which is likely as it is a very unusual query - don't use it.
>
> David J.
>
>