I'm attempting to truncate a table using Java with an Oracle database. My goal is to achieve this while avoiding SQL injection vulnerabilities. Here's the code I've tried:
String tableName = "employee";
String truncateQuery = "TRUNCATE TABLE ?";
try (PreparedStatement statement = connection.prepareStatement(truncateQuery)) {
statement.setString(1, tableName);
statement.executeUpdate();
}
However, when I execute this code, I encounter an "invalid table name" error. I'm aware that concatenating the table name directly into the query string ("TRUNCATE TABLE" + tableName) could lead to command injection vulnerabilities.
I've also confirmed that the table name is valid, as executing "TRUNCATE TABLE employee" directly in the database works fine.
My question is: Is there a way to use query parameters effectively in this scenario to avoid SQL injection while truncating a table using prepared statements in Java with an Oracle database?
I appreciate any guidance or suggestions on how to achieve this securely.
Is there a way to use query parameters effectively in this scenario to avoid SQL injection while truncating a table using prepared statements in Java with an Oracle database?
No you can't do that. As commenters have stated, an SQL table name (or a column name, an expression and so on) cannot be parameterized a PreparedStatment. Only values can be parameterized.
AFAIK, the same thing is true for JDBC drivers for all other database products.
How to avoid SQL injection and truncate table?
You can avoid generating the SQL strings at all, and prepopulate (say) a Map to translate user supplied table names to TRUNCATE statements for each (known) table which is safe for users to truncate.
Alternatively you can create a list of "safe to truncate" tables and validate the user-supplied table name against that ... and then generate the SQL for the TRUNCATE.
Alternatively you can ensure that users cannot supply the table name.
The bottom line is that parameterizing an SQL table name in a PreparedStatement would only give you a false sense of security. The bad guys could still cause mayhem by passing in a table name that shouldn't be truncated.