Summary: this tutorial shows you how to update data in a table from a Java program using JDBC.
To update existing data of a table, you follow the steps below:
- First, connect to the SQLite database.
- Next, prepare the UPDATE statement. For the
UPDATEstatement that uses parameters, you use the question marks (?) placeholder in theSETand WHERE clauses. - Then, instantiate an object the
PreparedStatementclass by calling the prepareStatement() method of theConnectionobject. - After that, set a value for each placeholder using the set* method of the
PreparedStatementobject, for example,setString(),setInt(), etc. - Finally, execute the
UPDATEstatement by calling theexecuteUpdate()method of thePreparedStatementobject.
The following program inserts three rows into the warehouses table that we created in the creating table tutorial.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 | package net.sqlitetutorial; import java.sql.Connection; import java.sql.DriverManager; import java.sql.PreparedStatement; import java.sql.SQLException; /** * * @author sqlitetutorial.net */ public class UpdateApp { /** * Connect to the test.db database * * @return the Connection object */ private Connection connect() { // SQLite connection string String url = "jdbc:sqlite:C://sqlite/db/test.db"; Connection conn = null; try { conn = DriverManager.getConnection(url); } catch (SQLException e) { System.out.println(e.getMessage()); } return conn; } /** * Update data of a warehouse specified by the id * * @param id * @param name name of the warehouse * @param capacity capacity of the warehouse */ public void update(int id, String name, double capacity) { String sql = "UPDATE warehouses SET name = ? , " + "capacity = ? " + "WHERE id = ?"; try (Connection conn = this.connect(); PreparedStatement pstmt = conn.prepareStatement(sql)) { // set the corresponding param pstmt.setString(1, name); pstmt.setDouble(2, capacity); pstmt.setInt(3, id); // update pstmt.executeUpdate(); } catch (SQLException e) { System.out.println(e.getMessage()); } } /** * @param args the command line arguments */ public static void main(String[] args) { UpdateApp app = new UpdateApp(); // update the warehouse with id 3 app.update(3, "Finished Products", 5500); } } |
First, you check the warehouse table before running the update program using the following SELECT statement.
1 2 3 4 5 6 | SELECT id, name, capacity FROM warehouses; |
Second, execute the UpdateApp program.
Third, query data from the warehouses table again using the same SELECT statement above.
In this tutorial, you have learned how to update data in the SQLite database from the Java program.