Apologies, as usual I didn't read the docs carefully enough.

On Tue, May 17, 2016 at 7:13 PM, Tom Lane <t...@sss.pgh.pa.us> wrote:

> Shay Rojansky <r...@roji.org> writes:
> > A user of mine just raised a strange issue... While it is possible to
> use a
> > parameter in a LIMIT clause, PostgreSQL does not seem to allow using one
> in
> > a FETCH NEXT clause. In other words, while the following works:
> > SELECT 1 LIMIT $1;
> > The following generates a syntax error:
> > SELECT 1 FETCH NEXT $1 ROWS ONLY;
> > Since LIMIT and FETCH NEXT are supposed to be equivalent this behavior is
> > odd.
>
> Per the SELECT reference page:
>
>     SQL:2008 introduced a different syntax to achieve the same result,
>     which PostgreSQL also supports. It is:
>
>         OFFSET start { ROW | ROWS }
>         FETCH { FIRST | NEXT } [ count ] { ROW | ROWS } ONLY
>
>     In this syntax, to write anything except a simple integer constant for
>     start or count, you must write parentheses around it.
>
> The comments about this in gram.y are informative:
>
>  * Allowing full expressions without parentheses causes various parsing
>  * problems with the trailing ROW/ROWS key words.  SQL only calls for
>  * constants, so we allow the rest only with parentheses.  If omitted,
>  * default to 1.
>
>                         regards, tom lane
>

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