Java Database Connectivity is basically a standard API(application interface) between the java programming language and various databases like Oracle, SQL, Postgres, SQL, etc. It connects the front end(for interacting with the users ) with the backend( for storing data).
Algorithm: Search/ Insert/ Delete/ Update in JDBC
In order to deal with JDBC standard 7 steps are supposed to be followed:
- Import the database
- Load and register drivers
- Create a connection
- Create a statement
- Execute the query
- Process the results
- Close the connection
Procedure:
- Creating a database irrespective of SQL or NoSQL. Creating a database using sqlyog and creating some tables in it and fill data inside it in order to search for the contents of a table. For example, the database is named “hotelman” and table names are “cuslogin” & “adminlogin”.
- Create a connection: Open any IDE where the java executable file can be generated following the standard methods. Creating a package further creating a class. Inside the package, open a new java file and type the below code for JDBC connectivity and save the filename with connection.java.
- Inserting details in a table using JDBC in the input sample image with parameters as follows
- “cuslogin” table has columns namely –
- name
- password
- address
- phone
- id
- Need is to insert new details inside the “cuslogin” table.
- “cuslogin” table has columns namely –
Input sample Image:
3.1: Initialize a string with the SQL query as follows
String sql=”insert into cuslogin values(‘neveropen’,’gfg’,’geeks@email.com’,’flat 1′,’1239087474′,10)”;
3.2: Initialize the below objects of Connection class, PreparedStatement class(needed for JDBC ) and connect with the database as follows
Connection con=null; PreparedStatement p=null; con=connection.connectDB();
3.3: Now, add the SQL query of step 3.1 inside PrepareStatement and execute it as follows
p =con.prepareStatement(sql); p.execute();
3.4: Open a new java file (here, its result.java) inside the same package and type the full code (shown below) for inserting the details of the customer in table “cuslogin”.
Note: Both the file’s viz result.java and connection.java should be inside the same package, else the program won’t give the desired output.
Implementation :
- Example 1 is Connection class of JDBC
- Example 2 is App(Main) class where connection class is used as calling object of Connection class in main class.
Example 1: Connection class
Java
// Java Program to Insert Details in a Table using JDBC// Connections class// Importing all SQL classesimport java.sql.*;public class connection { // object of Connection class // initially assigned NULL Connection con = null; public static Connection connectDB() { try { // Step 2 is involved among 7 in Connection // class i.e Load and register drivers // 2(a) Loading drivers using forName() method // name of database here is mysql Class.forName("com.mysql.jdbc.Driver"); // 2(b) Registering drivers using DriverManager Connection con = DriverManager.getConnection( "root", "1234"); // For DB here (custom sets) // root is the username, and // 1234 is the password // returning the object of Connection class // to be used in main class (Example2) return con; } // Catch block to handle the exceptions catch (SQLException | ClassNotFoundException e) { // Print the exceptions System.out.println(e); return null; } }} |
Example 2: App/Main Class where the program is compiled and run calling the above connection class object
Java
// Java Program to Insert Details in a Table using JDBC// Main class// Step 1: Importing DB classes// DB is SQL hereimport java.sql.*;// Main/App class of above Connection classpublic class GFG { // MAin driver method public static void main(String[] args) { // Step 2: Showing above Connection class i.e // loading and registering drivers // Initially assigning NULL parameters // to object of Connection class Connection con = null; PreparedStatement ps = null; // Step 3: Establish the connection con = connection.connectDB(); // Try block to check if exception/s occurs try { // Step 4: Create a statement String sql = "insert into cuslogin values('neveropen','gfg','geeks@email.com','flat 1','1239087474',10)"; // Step 5: Execute the query ps = con.prepareStatement(sql); // Step 6: Process the results ps.execute(); } // Optional but recommended // Step 7: Close the connection // Catch block to handle the exception/s catch (Exception e) { // Print the exception System.out.println(e); } }} |
Output:
Details added here: “neveropen” named customer details have been added.
