How to Resolve `java.sql.SQLException: Missing IN or OUT parameter at index: 1` Error

What are the best approaches to fix the `java.sql.SQLException: Missing IN or OUT parameter at index: 1` error?

PreparedStatement pstmt = connection.prepareStatement("SELECT * FROM users WHERE id = ?");
pstmt.setInt(1, userId);

The `java.sql.SQLException: Missing IN or OUT parameter at index: 1` error typically occurs when executing a stored procedure or prepared statement without providing required parameters. Understanding its causes and how to resolve it is crucial for smooth database operations.

String sql = "INSERT INTO employees (name, email) VALUES (?, ?);";
PreparedStatement pstmt = connection.prepareStatement(sql);
pstmt.setString(1, "John Doe");
pstmt.setString(2, "[email protected]");
pstmt.executeUpdate();

Causes

• No value was set for the parameter at the specified index.
• The index provided is out of range or not matching the number of parameters expected.
• The parameter being referenced may not be defined in the SQL query.

Solutions

• Ensure that all required parameters are set using the appropriate setter methods before executing the statement.
• Double-check that the index starts at 1 for the first parameter (PreparedStatement uses 1-based indexing).
• Verify that the SQL query matches the number of parameters being passed.

Mistake: Forgetting to call the setter method for a parameter.

Solution: Always ensure that you are calling the appropriate setter method for each IN parameter.

Mistake: Using 0-based indexing instead of 1-based when setting parameters.

Solution: Remember that PreparedStatement uses 1 as the starting index for parameters.