Why Does `executeQuery(String)` Cause SQL Syntax Errors with PreparedStatements?

Incorrect Method Invocation Causing Syntax Error in PreparedStatement Execution

When executing a SQL query using a PreparedStatement, it is important to adhere to the correct syntax and execution method to avoid syntax errors.

One common issue arises when attempting to execute the query by calling executeQuery(String) on the PreparedStatement object. This is incorrect, as it overrides the prepared query with the original query.

The correct approach is to call the method executeQuery() without any arguments, as demonstrated below:

PreparedStatement s = conn.prepareStatement(query);
s.setInt(1, intValue);
s.setString(2, strValue);        
rs = s.executeQuery(); // OK!

By making this adjustment, you ensure that the prepared query is executed correctly, eliminating the "You have an error in your SQL syntax" error.

Additional Notes:

• It is crucial to ensure proper resource management by closing the Connection, Statement, and ResultSet objects in a try-with-resources block to prevent resource leaks.
• The specific error message in your case, "You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '? or MemberName = ?' at line 1", indicates that MySQL encountered an unrecognized syntax element "?" in the prepared query, highlighting the need for correct parameter binding.

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