Hi there, thank you for your advice. I really learned from what you wrote. But I still have some prolem. When I was trying to set the Access table to refuse duplicate values, the program simply stopped and gave error message when there were duplicated values. So I want to first read what are already in the table into an array, lets say array A1, and compare the values I intent to insert into the table with the values in A1. If a value has already been in A1, I will discard it and go to the next value. If the next value is not in A1, I will put it into an array A2. After this process ends, I then will insert the values in A2 into the Access table. My problem is that the values in A2 contains some values in A1. I do not know why.

In reply to Re: Re: How do I avoid inserting duplicate numbers into an Access table? by Anonymous Monk
in thread How do I avoid inserting duplicate numbers into an Access table? by luoina

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