On 05/01/10 03:58, Jasen Betts wrote:
On 2010-04-30, silly sad<s...@bankir.ru> wrote:
suppose i request
SELECT foo(t.x) FROM t LIMIT 1;
Whither it DEFINED how many times foo() will be executed?
foo will be executed repeatedly until it returns a result or all the
rows in t are exhausted.
May anyone rely on it?
not sure
Or we have to avoid this non SQLish trick?
This will execute it once (or not at all where t has no rows)
SELECT foo(x) FROM (SELECT x FROM t LIMIT 1) as bar;
this subselect "isolation" looks like a safe way.
Unlike LIMITed select looks unpredictable to me.
Thanx for assistance :)
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