DBGrid Lookup field problems

[bobstery]

I am trying to insert a row to a database using a dbgrid. I have four lookup fields, each one relating to a different table. However when I access a lookup fields drop down menu and select an item I get the following error message:

Project name.exe raised exception EOleException with message 'An unknown error has occurred', Process stopped. Use step or run to continue.

This message appears everytime after enetering a value until data is present in each of the lookup fields. So if I try to insert a value in a lookup field and there is none present in the other 3, 3 error messages will appear after pressing F9 after each message.

Why do I get this message as the lookup fields are retrieving data from different tables?

 

[bNasty]

Hi,
You are not using BDE, right? Well, you did not say what you are using lookup-fields for. If you could give a more detailed description it would be much better, but it seems to me that those error-messages are to be expected, since you are trying to (obviously) post record to table without all the required fields being there

 

[bobstery]

I get the error messages before posting i.e. when entering a value into any field and then tabbing, causes the error(s) depending on which lookup fields have a value.

I am using the lookup fields so that the user doesn't see the code reference, but a more friendly representation of what is wanted e.g. I show the owner's name in the DBGrid using a lookup field, I store the reference however in the table e.g. 001. In the owners table 001 has a name of Brian. Therefore when entering a new value using the DBGrid I want to show the names rather than the codeRef, therefore I use a lookup field which automatically genrates the right value for the code.

I do this for another four fields, that each correspond to a different table. So why do I get the error messages if I am not posting the data. After each error message appears I can go on and post the data into the table, with no errors, however I don't want error messages popping up all the time when entering data.

Thanks