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Message
De
16/11/2007 09:48:40
 
Information générale
Forum:
Visual FoxPro
Catégorie:
Base de données, Tables, Vues, Index et syntaxe SQL
Versions des environnements
Visual FoxPro:
VFP 9
OS:
Windows XP
Network:
Windows XP
Database:
Visual FoxPro
Divers
Thread ID:
01268865
Message ID:
01269392
Vues:
12
>>>>Is that correct? I thought that SQL aliases have nothing to do with A-J aliases for work areas.
>>>>
>>>>>It's a bad idea to use one leter meaningless table aliases in a query. It makes the query totally unreadable. It also could be dangerous because letters A-J are reserved for workareas 1-10.
>>>
>>>From my testing, you are correct: Message#1154483
>>
>>It's no longer a problem, but at one time, you could get unexpected results with something along these lines:
>>
>>
>>SELECT 1
>>USE MyTable && now in workarea A
>>
>>SELECT ... ;
>>  FROM AnotherTable A ;
>>  ...
>>
>>
>>VFP would get confused over what A meant.
>>
>>Tamar
>
>What was that time?
>In my experience, (V)FP was NEVER confused in the scenario above. Maybe the programmer, but that's always a possibility.

My example may be too simple, but I definitely saw cases where the use of single letter aliases in queries caused a problem.

Tamar
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