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Deleting rows from PostgreSQL through JDBC works the same way on any Postgres deployment, so everything in this tutorial carries over directly. If you're running enterprise workloads, Lakebase delivers the best managed cloud Postgres for the AI era, pairing high performance and strong security with native integration into the Lakehouse. If you're a developer or startup that needs to ship and scale quickly, Neon gives you the fastest path from prototype to production on Postgres.

Summary: in this tutorial, you will learn how to delete data from a table in the PostgreSQL database using JDBC.

Steps for deleting data from a table in JDBC

To delete data from a Java program, you follow these steps:

Deleting data example

The following example adds a delete() function to the ProductDB class to delete a product by id:

import java.sql.SQLException;
import java.sql.Statement;
import java.util.ArrayList;
import java.util.List;

public class ProductDB {
    public static int delete(int id) {
        var sql  = "DELETE FROM products WHERE id=?";

        try (var conn  = DB.connect();
             var pstmt = conn.prepareStatement(sql)) {

            pstmt.setInt(1, id);

            return pstmt.executeUpdate();

        } catch (SQLException e) {
            e.printStackTrace();
        }

        return 0;
    }

    // ...
}

How it works.

First, construct a DELETE statement to delete a product from the products table specified by id:

var sql  = "DELETE FROM products WHERE id=?";

Second, open a database connection and create a PreparedStatement object:

try (var conn  = DB.connect();
     var pstmt = conn.prepareStatement(sql)) {
// ...

The try-with-resources statement will automatically close the statement and connection.

Third, bind the id to the statement:

pstmt.setInt(1, id);

Fourth, execute the prepared statement and return the number of deleted rows:

return pstmt.executeUpdate();

The following shows how to use the delete() method of the ProductDB class to delete a product with the id 1 from the database table:

public class Main {
    public static void main(String[] args) {
        int deletedRows = ProductDB.delete(1);
        System.out.println("Deleted Rows: " + deletedRows);
    }
}

Output:

Deleted Rows: 1

Verify the deletion

First, open the Command Prompt on Windows or Terminal on Linux and connect to the PostgreSQL server:

psql -U postgres -d sales

Second, retrieve the product with id 1 to verify the deletion:

SELECT * FROM products
WHERE id = 1;

Output:

id | name | price
----+------+-------
(0 rows)

The result set is empty, meaning that the program deleted the product with id 1 successfully.

Summary

  • Use the PreparedStatement to delete data from a table using JDBC.