How to Use the LIKE Wildcard with Prepared Statements in SQL?

Using "like" Wildcard in Prepared Statement

Prepared statements provide a secure and efficient way to execute SQL queries, especially when dealing with user input. When using the LIKE keyword with prepared statements, it's crucial to understand where to insert the wildcard.

In the provided code, you can directly add the 'keyword%' to the value being set in pstmt.setString(1, notes). This means modifying the code to:

PreparedStatement pstmt = con.prepareStatement(
      "SELECT * FROM analysis WHERE notes like ?");
pstmt.setString(1, notes + "%");
ResultSet rs = pstmt.executeQuery();

By adding the wildcard directly to notes, you're effectively appending it to the value during query execution. This allows you to perform prefix-match searches.

In case of suffix-match or global-match searches, modify the code accordingly:

Suffix-match:

pstmt.setString(1, "%" + notes);

Global-match:

pstmt.setString(1, "%" + notes + "%");

Remember, it's critical to properly escape special characters like % and _ in the notes string before adding the wildcard. This prevents ambiguous patterns and ensures accurate results.

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