Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> writes:
> * When we have a non-nullable expression in a sub-select's targetlist,
> and it's below an outer join, replace the expression by
> CASE WHEN flag_var THEN original_expression ELSE NULL END
> and then flatten as normal.
I don't understand how this gets you any further ahead. Doesn't it just move
the problems you have now with the original_expression to flag_var instead?
--
Gregory Stark
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