Re: [HACKERS] [GENERAL] workaround for lack of REPLACE() function

Tom Lane wrote:
> Joe Conway <mail(at)joeconway(dot)com> writes:
>
>>The only remaining problem is that this causes opr_sanity to fail based
>>on this query: ...
>>This fails because I implemented text_substr() and bytea_substr() to
>>take either 2 or 3 args. This was necessary for SQL92 spec compliance.
>
>
> Rather than loosening the opr_sanity test, I'd suggest setting this
> up as two separate builtin functions. They can call a common
> implementation routine if you like. But a runtime test on the number
> of arguments doesn't offer any attractive improvement.

I took Tom's advice and added wrapper functions around text_substr() and
bytea_substr() to cover the 2 argument case.

I also added tests to strings.sql to cover substr() on toasted columns
of both text and bytea.

If there are no objections, please apply.

Thanks,

Joe