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Performance/memory usage
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De
28/10/1999 13:55:25
 
 
À
28/10/1999 10:32:49
Information générale
Forum:
Visual FoxPro
Catégorie:
Base de données, Tables, Vues, Index et syntaxe SQL
Divers
Thread ID:
00282911
Message ID:
00283249
Vues:
16
>>>If I have a large file with, say 100 fields in it and 1000 records. If I need only 10 of the fields to be updated, will my app perform better if my SQL gets only those 10 fields, instead of all fields? Also, if I have to orphan a field in a free table because it's name is a reserved word in VFP, what kind of memory issues occur if I continue to retrieve this field (25 characters) in a SQL select *; blah,blah,blah?
>>>
>>>TIA
>>>Mike
>>
>>Yes, the SQL will perform better if you only get those 10 fields. Why do you need to orphan the field? I have FoxDOS code that I'm simply recompiling and running under VFP that has fields that are reserved words and I'm not having any problems.
>
>Craig:
>
>Under the heading of Stupid VFP Tricks, try the following:
>
>CREATE TABLE _vfp (formcount I, name c(50))
>APPEND
>
>And even stupider VFP Tricks:
>
>CREATE TABLE _VFP (formcount I, name c(50), activeform m)
>APPEND

Ed,

I have no doubt that certain field names will cause problems if using reservered words. Others obviously don't, since I'm not having problems with them.
Craig Berntson
MCSD, Microsoft .Net MVP, Grape City Community Influencer
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