MySQL PreparedStatement Syntax Error: Why is `executeQuery()` Failing with `?` Placeholders?

MySQL Syntax Error: Understanding the PreparedStatement Syntax

Your Java code using a PreparedStatement to execute a query is encountering a MySQL syntax error (error number 1064). This error is typically thrown when there's an issue with the SQL syntax itself.

Identifying the Source of the Error:

The provided code shows that you're attempting to execute a query containing placeholders represented by "?". MySQL doesn't interpret the "?" characters as placeholders and instead treats them as part of the SQL statement.

Solution: Utilizing the Argumentless executeQuery() Method

To resolve the issue, you need to use the prepared statement's executeQuery() method without specifying the query string as an argument.

PreparedStatement s = conn.prepareStatement(query);
s.setInt(1, 2);
s.setString(2, "zen");
ResultSet rs = s.executeQuery(); // Correct syntax

By omitting the query string in executeQuery(), you're allowing the prepared statement to execute the previously defined query with the provided parameter values.

Caution: Resource Leakage

Your code currently lacks proper handling of resource allocation and deallocation. It's recommended to employ the JDBC idiom of closing all acquired resources (Connection, Statement, ResultSet) in a finally block of the try block. Otherwise, your application may exhaust the database's resources over time, leading to instability.

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