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Is MAX() a good choice where GROUP BY?
Message
Information générale
Forum:
Visual FoxPro
Catégorie:
Base de données, Tables, Vues, Index et syntaxe SQL
Divers
Thread ID:
01676115
Message ID:
01676131
Vues:
44
>>>Here is an example:
>
>*-- Table1
>*-- Strucutre:
>FIELD1     FIELDX    FIELDY
>2
>4
>2
>2
>1
>4
>4
>
>*-- Table 2
>*-- Structure
>FIELD1     FIELD2    FIELD3
>1               'ABC'      '123'
>2               'XYZ'      '456'
>3              'DFD'      '333'
>4              'DDF'      '444'
>
>*-- Resulting query should be
>FIELD1     FIELD2     FIELD3
>1               'ABC'      '123'
>2               'XYZ'      '456'
>4              'DDF'      '444'
>
>>>
>>>Now that I wrote the example, above, I think I can SELECT from Table2 and JOIN Table1 on FIELD1.
>
>
>I think you do not even need a join for this, you can just select the records from Table2 that have a FK in Table 1, like:
>
>
>SELECT Field1, Field2, Field3 FROM Table2 WHERE Field1 IN (SELECT Field1 FROM Table1)
>
>
>As you are not using the FieldX and FieldY at all

The real case (my example is somewhat simplified) is more involved. But maybe what you suggest is what I need.
Thank you.
"The creative process is nothing but a series of crises." Isaac Bashevis Singer
"My experience is that as soon as people are old enough to know better, they don't know anything at all." Oscar Wilde
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