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Codage, syntaxe et commandes
Got the following from a previous message that you posted.
>The _TALLY after a query holds the number of records in the result not the >number of record matching the query criteria. In VFP9 a query with >aggreagate function, like SUM()/ MAX()/e.t.c, without GROUP BY clause >returns a single record with all nulls as required by ANSI SQL standard. >It's documented in SET ENGINEBEHAVIOR help topic. It actualy makes your >code simplier.
>SELECT NVL(SUM(prem+expc+teri+late_fee+penalty),0) ;
> FROM cur_ar WHERE LEFT(ALLTRIM(ar_type),1) == "C" ;
> INTO ARRAY arTotalc
>lnarTotalc = arTotalc
It seems that if you add a GROUP BY clause to a MIN,MAX,COUNTY,SUM function SQL it makes the SQL results as in VFP8 - when there are no matching records. Either with or without the NVL, when there are no matching records the result set is empty and _tally is 0.
Do you find this to be true?
Brenda
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