Write a Java program to connect to a SQL DataBase.

Category : Java | Sub Category : Java Programs | By Runner Dev Last updated: 2021-04-19 14:43:52 Viewed : 285


JDBC is a standard Java API for database-independent connectivity between the Java programming language and a wide range of databases. This application program interface lets you encode the access request statements, in Structured Query Language (SQL). They are then passed to the program that manages the database. It mainly involves opening a connection, creating a SQL Database, executing SQL queries and then arriving at the output. Let’s see an example code to create a database and establish a connection and run the queries.
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
package runnerdev;
import java.sql.*;
import java.sql.DriverManager;
public class Example {
// JDBC driver name and database URL
static final String JDBC_DRIVER = "com.mysql.jdbc.Driver";
static final String DB_URL = "jdbc:mysql://localhost/emp";
// Database credentials
static final String USER = "root";
static final String PASS = "edureka";
public static void main(String[] args) {
Connection conn = null;
Statement stmt = null;
try{
//STEP 2: Register JDBC driver
Class.forName("com.mysql.cj.jdbc.Driver");
//STEP 3: Open a connection
System.out.println("Connecting to database...");
conn = DriverManager.getConnection(DB_URL,"root","edureka");
//STEP 4: Execute a query
System.out.println("Creating statement...");
stmt = conn.createStatement();
String sql;
sql = "SELECT id, first, last, age FROM Employees";
ResultSet rs = stmt.executeQuery(sql);
//STEP 5: Extract data from result set
while(rs.next()){
//Retrieve by column name
int id = rs.getInt("id");
int age = rs.getInt("age");
String first = rs.getString("first");
String last = rs.getString("last");
//Display values
System.out.print("ID: " + id);
System.out.print(", Age: " + age);
System.out.print(", First: " + first);
System.out.println(", Last: " + last);
}
//STEP 6: Clean-up environment
rs.close();
stmt.close();
conn.close();
}catch(SQLException se){
//Handle errors for JDBC
se.printStackTrace();
}catch(Exception e){
//Handle errors for Class.forName
e.printStackTrace();
}finally{
//finally block used to close resources
try{
if(stmt!=null)
stmt.close();
}catch(SQLException se2){
}// nothing can be done
try{
if(conn!=null)
conn.close();
}catch(SQLException se){
se.printStackTrace();
}//end finally try
}//end try
System.out.println("Goodbye!");
}//end main
} // end Example

On executing the above code, it will establish the connection to the database and retrieve the data present in the database.

1
2
3
4
5
6
7
Connecting to database...
Creating statement...
ID: 100, Age: 18, First: Zara, Last: Ali
ID: 101, Age: 25, First: Mahnaz, Last: Fatma
ID: 102, Age: 30, First: Zaid, Last: Khan
ID: 103, Age: 28, First: Sumit, Last: Mittal
Goodbye!

Search
Related Articles

Leave a Comment:
Carole Ernest
at 2022-01-06 00:54:47
Good job on the new site! Now go ahead and submit it to our free directory here https://bit.ly/addyoursitehere
Teena Wolak
at 2022-04-21 00:14:14
Hello. It is with sad regret to inform you TopDataList.com is shutting down. We have made all our databases available for you for a once off fee. Visit us on TopDataList.com
Gretta Helbig
at 2022-04-30 17:08:16
Hello If you ever need Negative SEO or a de-rank strategy, you can hire us here https://www.speed-seo.net/product/negative-seo-service/