---
title: 'PostgreSQL JDBC: Updating Data'
page_title: 'PostgreSQL JDBC: Updating Data'
page_description: 'In this tutorial, you will learn how to update data in a PostgreSQL database using JDBC API.'
prev_url: 'https://www.postgresqltutorial.com/postgresql-jdbc/update/'
ogImage: ''
updatedOn: '2024-02-02T04:57:49+00:00'
enableTableOfContents: true
previousLink:
  title: 'PostgreSQL JDBC: Querying Data'
  slug: 'postgresql-jdbc/query'
nextLink:
  title: 'PostgreSQL JDBC: Delete Data from Table'
  slug: 'postgresql-jdbc/delete'
---

**Summary**: in this tutorial, you will learn how to update data in a PostgreSQL database using JDBC API.

## Steps for updating data

To update data in a table of a PostgreSQL database, you follow these steps:

- Create a database connection by instantiating a `Connection` object.
- Create a `PreparedStatement` object.
- Execute an [UPDATE statement](../postgresql-tutorial/postgresql-update) by calling the `executeUpdate()` method of the `PreparedStatement` object.
- Close the `PreparedStatement` and `Connection` objects by calling the `close()` method.

## Updating data example

The following defines the `update()` method that changes the `name` and `price` of a product specified by product id:

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

public class ProductDB {

    public static int update(int id, String name, double price) {
        var sql  = "UPDATE products "
                + "SET name = ?, price= ? "
                + "WHERE id = ?";

        int affectedRows = 0;

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

            pstmt.setString(1, name);
            pstmt.setDouble(2, price);
            pstmt.setInt(3, id);

            affectedRows = pstmt.executeUpdate();

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

 // ...
}
```

How it works.

First, construct an `UPDATE` statement that updates the `name` and `price` of a product by id:

```java
 var sql  = "UPDATE products "
                + "SET name = ?, price= ? "
                + "WHERE id = ?";
```

Second, initialize a variable that stores the number of affected rows:

```java
int affectedRows = 0;
```

Third, establish a connection and create a `PreparedStatement` object:

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

Fourth, bind values to the statement:

```java
pstmt.setString(1, name);
pstmt.setDouble(2, price);
pstmt.setInt(3, id);
```

Fifth, execute the statement and assign the return value of the `executeUpdate()` method to the `affectedRows` variable:

```java
affectedRows = pstmt.executeUpdate();
```

Finally, return the number of affected rows:

```java
return affectedRows;
```

The following shows how to use the `ProductDB` class to update the name and price of the product:

```java
public class Main {
    public static void main(String[] args) {
        int updatedRows = ProductDB.update(1, "Phone Cover", 22.49);
        System.out.println("Updated Rows: " + updatedRows);
    }
}
```

Output:

```plaintext
Updated Rows: 1
```

## Verify the update

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

```plaintext
psql -U postgres -d sales
```

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

```
SELECT * FROM products
WHERE id = 1;
```

## Summary

- Use a `PreparedStatement` object to update data in a table from a Java program.