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Solved

Error on ADO Table

Posted on 2003-02-26
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Last Modified: 2010-05-18
I'm using Delphi 7 and I'm trying to connect to MSSQL 7 using ADO components

ado conection
and ado table

when I run the application it sends the following exception
 EVariantTypeCastError 'Could not convert variant of type(null) into type(string)

How Can I avoid this?

Thanks
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Question by:mavi740218
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7 Comments
 

Expert Comment

by:GummiStori
ID: 8026881
What are you trying to do? (open, etc...)
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Author Comment

by:mavi740218
ID: 8026955
I just set Active property to True, I just have a dbgrid and a dbnavigator I can see the information but the error raises every time
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LVL 27

Accepted Solution

by:
kretzschmar earned 100 total points
ID: 8027067
if this does only happen within the ide
-> then ignore

if this also happens outside the ide
(close the ide and run your exe)
-> then try to create persistent fields
( doubleclick on tadotable
, rightclick on the poped-up field editor
, select "Add All Fields" from the popup-menu)

then you may evaluate which field causes this error
(maybe its a large Varchar-field) and try different fieldtypes of tfield-property)

hope thats it

meikl ;-)
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LVL 1

Assisted Solution

by:khalil_moghaddam
khalil_moghaddam earned 100 total points
ID: 8036062
what about your DataSet? do u have Calculated field?
did you use field editor or set field type manually?
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Expert Comment

by:CleanupPing
ID: 9317059
mavi740218:
This old question needs to be finalized -- accept an answer, split points, or get a refund.  For information on your options, please click here-> http:/help/closing.jsp#1 
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LVL 10

Expert Comment

by:kacor
ID: 9981457
No comment has been added lately, so it's time to clean up this TA.
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