Why we get these messages: Cannot select a record in Customers (CustTable). Customer account: , . The SQL database has issued an error.

Sometimes we are getting these messages

Cannot select a record in Customers (CustTable). Customer account: , . The SQL database has issued an error.

We are also getting them on SalesTable, EmplTable.

How to know more info about such errors and how to fix them.

Any suggestions will be appreciated.

Thanks

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