Grouping a set of INSERT or, UPDATE or, DELETE commands (those produce update count value) and execute them at once this mechanism is known as a batch update.
If you pass quires with parameters using batch update it is known as a parameterized batch update.
Generally, to perform batch updates you need to add all the required statements using the addBatch() method and execute them using the executeBatch() method as:
//Creating a Statement object
Statement stmt = con.createStatement();
//Setting auto-commit false
con.setAutoCommit(false);
//Adding the statements to batch
stmt.addBatch("INSERT INTO Sales VALUES ('KeyBoard', 'Amith', 'January', 1000, 'Hyderabad')");
stmt.addBatch("INSERT INTO Sales VALUES ('Earphones', 'SUMITH', 'March', 500, 'Vishakhapatnam')");
stmt.addBatch("INSERT INTO Sales VALUES ('Mouse', 'Sudha', 'September', 200, 'Vijayawada')");
//Executing the batch
stmt.executeBatch();If you observe the above code here, we are adding the certain part of the statement to the batch again and again instead of this, you can perform a parameterized batch update where you use a prepared statement and create a query with place holders and pass values to these place holders using the setter methods.
While adding values you need to add each set of values of the query to the batch and then execute them at once.
Creating a parameterized Batch update
To create a parameterized batch update, you need to create a prepared statement to insert, update, or, delete values with place holders.
Set values to the placeholders, parameters using the setXXX() statements. Add each set of values to the batch using the addbatch() method, Finally execute the batch using the executeBatch method.
Note: Before adding statements to the batch you need to turn the auto commit off using the con.setAutoCommit(false) and, after executing the batch you need to save the changes using the con.commit() method.
Example
Assume we have created a table named Sales in the database with the following description:
+-------------------+--------------+------+-----+---------+-------+ | Field | Type | Null | Key | Default | Extra | +-------------------+--------------+------+-----+---------+-------+ | Product_Name | varchar(255) | YES | | NULL | | | Name_Of_Customer | varchar(255) | YES | | NULL | | | Month_Of_Dispatch | varchar(255) | YES | | NULL | | | Price | int(11) | YES | | NULL | | | Location | varchar(255) | YES | | NULL | | +-------------------+--------------+------+-----+---------+-------+
This example tries to insert a set of statements into the above mentioned table using parameterized batch update.
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.Statement;
public class ParameterizedBatchUpdate {
public static void main(String args[])throws Exception {
//Getting the connection
String mysqlUrl = "jdbc:mysql://localhost/testDB";
Connection con = DriverManager.getConnection(mysqlUrl, "root", "password");
System.out.println("Connection established......");
//Creating a Statement object
Statement stmt = con.createStatement();
//Setting auto-commit false
con.setAutoCommit(false);
PreparedStatement pstmt = con.prepareStatement("INSERT INTO Sales VALUES (?, ?, ?, ?, ?)");
pstmt.setString(1, "KeyBoard");
pstmt.setString(2, "Amith");
pstmt.setString(3, "January");
pstmt.setInt(4, 1000);
pstmt.setString(5, "Hyderabad");
pstmt.addBatch();
pstmt.setString(1, "Earphones");
pstmt.setString(2, "Sumith");
pstmt.setString(3, "March");
pstmt.setInt(4, 500);
pstmt.setString(5, "Vishakhapatnam");
pstmt.addBatch();
pstmt.setString(1, "Mouse");
pstmt.setString(2, "Sudha");
pstmt.setString(3, "September");
pstmt.setInt(4, 500);
pstmt.setString(5, "Vishakhapatnam");
pstmt.addBatch();
//Executing the batch
stmt.executeBatch();
//Saving the changes
con.commit();
System.out.println("Records inserted......");
}
}Output
Connection established...... Records inserted......