Locate field with null value

Posted on 2002-04-28
Last Modified: 2012-05-04
I am using interbase as database with delphi 5.
i am using TIBQuery

Now in a table one field contains Null
i want to use locate function locate this field where value is null. Its now working.

Do you have any suggestions


Question by:rajniyadav
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Expert Comment

ID: 6976398
Hi rajniyadav,

select * from sometable
where some_field is NULL

Author Comment

ID: 6976820
i want to user
Query.Locate function
Through sql it is working but i want to user locate function.

Expert Comment

ID: 6976843
something like this?

  Query1.Locate('STR', NULL, []);

STR - name of field where can be NULL
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Author Comment

ID: 6976989
when i am doing this locate function returns false even though there is one record with null.
LVL 27

Accepted Solution

kretzschmar earned 100 total points
ID: 6977577
? maybe
as the values in the locate-method are internal variants you could try

Query1.Locate('STR', varNull, []); //or varEmpty

just a guess

meikl ;-)


Author Comment

ID: 6979294
kretzschmar that works but i have one more problem.

Since i have more than on fields value to locate can u tell how can i store those values in a variable and use it in locate function

i made one string variable even variant and stored all the fieldvalues seperated with commas in that but it is not locating the right record.
And if i directly give the value in hte locate function it does locates

Can u help in that.
LVL 27

Expert Comment

ID: 7213588
even not tested, but try

Query1.Locate('FIELD1;FIELD2;FIELD3;FIELD4', VarArrayOf([varNull,varNull,varNull,varNull]), []); //or varEmpty

seems i got no notification at april

thanks for the points

meikl ;-)

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