Thank you Dominic and Keith for your replies
The reason i asked this is that i have a query in wich one condition
filtering the recordset involves
an UDF and this UDF needs to be processed after all table filters have
been applied
Illustration :
additionnal table :
CREATE TABLE t2 (
a TEXT PRIMARY KEY,
b INTEGER,
c REAL);
UDF :
proc CallUDF {key} {
if{[dict exists $myDict $key]} {
dict get $myDict $key /* returns a value stored in myDict */
} else {error}
}
db function CallUDF -deterministic CallUDF
If i do :
SELECT *
FROM t1 CROSS JOIN t2
WHERE t1.b > 10
AND t2.a = t1.a and t2.c < 0
AND CallUDF(t2.a) <> 0
Even though "CROSS JOIN" garanties that t2 is traversed after t1 has
been filtered on "t1.b > 10",
it seems there is no garanty when t2 is traversed, that the filter
CallUDF(t2.a) <> 0 is evaluated *after*
filters "t2.b = t1.b and t2.c < 0".
In this case the sole solution we found is :
SELECT *
FROM t1, t2
WHERE t1.b > 10
AND t2.a = t1.a and t2.c < 0
GROUP BY t2.a
HAVING CallUDF(t2.a) <> 0
Thank again
Jean-Baptiste
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