Re: Syntax of xmltable function - Mailing list pgsql-hackers

Pavel Stehule <pavel.stehule@gmail.com> writes:
> The SQL/XML syntax is:

> XMLTABLE (
>   xmlquery
>   PASSING xmldocument
>   [COLUMNS columns_list] )

> columns_list := column_list ',' colname

> colname := colname datatype [DEFAULT value] [PATH text]

> The DEFAULT clause is before PATH clause.

> A Oracle db uses little bit different syntax - the DEFAULT and PATH clause
> are in different order. This is little bit better for Postgres too - now I
> can use a_expr in DEFAULT clause - what can be little bit better for other
> than text types.

> What should be preferrable? ANSI SQL syntax or Oracle syntax? This is not
> often task - I didn't find any example with DEFAULT clause for Oracle.

ISTM that the ordering of those two clauses is totally arbitrary, and
that if you're going to worry about Oracle at all, it'd be best to allow
both orderings.

                        regards, tom lane