Linking against null-fields.

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От Alexander Deruwe
Тема Linking against null-fields.
Дата
Msg-id 20011009112958.074132178C9@tartarus.telenet-ops.be
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Hey all,

I'm sorry if this question came up before, I couldn't find it in the 
archives..

Suppose I have two tables:

table File: contains alot of fields + 'driver' field, which refers to another 
table. I did not 'reference' it when creating the database because 
null-values have to be possible for this field.

Now, if in this File-table the field 'driver' is not filled in, the row will 
not be included in a query such as this one:

SELECT f.ID, d.NAME FROM FILE f, DRIVER d WHERE (d.ID = f.DRIVER);

However, the only reason I have this query set up as this is to get the name 
of the driver easily, if one is set.

How can this be helped? Should I just get the driver ID as a field, and then 
do a second query on that?

Thanks,

Alexander Deruwe


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