Re: BUG #16176: NULL value returned by category_sql argument to crosstab() causes segmentation fault

On 12/23/19 1:49 PM, Tom Lane wrote:
> Joe Conway <mail(at)joeconway(dot)com> writes:
>> Pushed that way to all supported branches.
>
> Hmm, why'd you use ERRCODE_SYNTAX_ERROR, and not say
> ERRCODE_NULL_VALUE_NOT_ALLOWED?

To be consistent with the error just above:
--------------------
/*
* The provided categories SQL query must always return one column:
* category - the label or identifier for each column
*/
if (spi_tupdesc->natts != 1)
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
errmsg("provided \"categories\" SQL must " \
"return 1 column of at least one row")));
--------------------

Also, the argument itself is a SQL statement, and it isn't NULL, it just
produces a NULL value as one (or more) of its output rows. It seems like
ERRCODE_NULL_VALUE_NOT_ALLOWED might be confusing.

But I am not married to ERRCODE_SYNTAX_ERROR if you think it ought to be
changed.

Joe
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