Using multiple INNER JOIN in Microsoft Access SQL
This article explores a common error encountered when performing multiple INNER JOIN operations in a Microsoft Access query. Users reported that queries returned syntax errors due to missing operators.
The problem is that the Access query requires parentheses when doing multiple joins, and the parentheses are missing from the user code. Access requires parentheses to ensure that join conditions are evaluated correctly.
To solve this problem, we provide a modified query:
FROM ((tbl_employee INNER JOIN tbl_netpay ON tbl_employee.emp_id = tbl_netpay.emp_id) INNER JOIN tbl_gross ON tbl_employee.emp_id = tbl_gross.emp_ID) INNER JOIN tbl_tax ON tbl_employee.emp_id = tbl_tax.emp_ID;
The modified query encloses the first set of INNER JOIN operations in parentheses. This ensures that the query evaluates these joins before executing the second INNER JOIN.
Finally, users are advised to use the Access Query Designer whenever possible. The designer automatically adds necessary brackets, simplifying the connection process and reducing potential errors.
The above is the detailed content of Why Do Multiple INNER JOINs in Access SQL Require Parentheses?. For more information, please follow other related articles on the PHP Chinese website!

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