MS ACCES DELPHIE MASTER/SLAVE PROBLEM

I use ms access tables with not indexes just a jointrelation between to
table. In my case a school classe code as master and a list of books for
the slave table so when on one gride I click the classe I get all the book
needed for that class
In the slave grid (table) itis not probleme to delete a book. But when I put
twice the same book in the table and want to delete one of them I get an
EOle Exception with the message "information about the column is not
suficient or incorrect. Too many ligne are affected.
When I carry on with the step by step commande I come to a message teeling
me that the lign doesn 't exist.
As anyone a clue why I cannot delete this ligne double.
thanks
claude


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