Re: Let-bindings in SQL statements

On Thu, 26 Jan 2012 06:37:49 -0800 (PST), Jon Smark wrote about
[GENERAL] Let-bindings in SQL statements:

>Is it possible to do the equivalent of let-bindings in a pure SQL
>function? I have a SELECT that invokes "now" multiple times.  It would
>be nicer to do it only once and reuse the value.  Something like this:
>
>LET right_now = SELECT now () IN
>SELECT * FROM my_table WHERE right_now >= start AND ...
>
>In PL/pgSQL this is easy, but I wonder about SQL...

Try using CURRENT_TIMESTAMP instead. In fact, CURRENT_TIMESTAMP is
more traditional SQL than now(). I don't have an ANSI standard handy,
so I cannot be certain when now() was added, if ever; but I have been
using CURRENT TIMESTAMP (space instead of vinculum) under DB2 for 20
years or more.
--
Regards,

Dave [RLU #314465]
*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*
dwnoon(at)ntlworld(dot)com (David W Noon)
*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*