Why Does My PreparedStatement Result in a 'You Have an Error in Your SQL Syntax' Exception in MySQL?

You have an Error in Your SQL Syntax when Using PreparedStatement

Problem:

When executing a query using a PreparedStatement in Java, a MySQLSyntaxErrorException occurs with the error message: "You have an error in your SQL syntax... near '? or MemberName = ?'."

Code:

String query = "select MemberID, MemberName from members where MemberID = ? or MemberName = ?";
Connection conn = DriverManager.getConnection(DATABASE_URL, USERNAME, PASSWORD);
PreparedStatement s = conn.prepareStatement(query);
s.setInt(1, 2);
s.setString(2, "zen");
ResultSet rs = s.executeQuery(query);

Cause:

The syntax error is caused by the question mark (?) in the SQL query. MySQL interprets it as a literal question mark, not as a parameter placeholder. This results in invalid SQL syntax.

Solution:

To resolve the issue, replace the question mark in the SQL query with a named parameter. This will allow the PreparedStatement to correctly bind the parameter values:

String query = "select MemberID, MemberName from members where MemberID = :member_id or MemberName = :member_name";

In the Java code, use the PreparedStatement#setString method to set the named parameters:

s.setString("member_id", "2");
s.setString("member_name", "zen");

Alternatively, you can use the argumentless s.executeQuery() method instead of s.executeQuery(query) to prevent overriding the prepared query with the original query.

Resource Leak:

Note that the provided code has a resource leak issue. The Connection, Statement, and ResultSet objects should be closed in a finally block to prevent resource exhaustion.

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