MySQL – Rename Views


MySQL – Rename View



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Renaming Views in MySQL

The MySQL RENAME TABLE statement in MySQL is generally used to rename the name of a table. But this statement can also be used to rename views because views are typically virtual tables created by a query.

Before renaming a view, we need to ensure that no active transactions are being performed on the view using its old name. It is, however, recommended to delete the existing view and re-create it with a new name instead of renaming it.

Syntax

Following is the basic syntax of the RENAME TABLE query to rename a view in MySQL −


RENAME TABLE original_view_name 
TO new_view_name;

Example

First of all, let us create a table with the name CUSTOMERS using the following query −


CREATE TABLE CUSTOMERS(
   ID int NOT NULL,
   NAME varchar(20) NOT NULL,
   AGE int NOT NULL,
   ADDRESS varchar(25),
   SALARY decimal(18, 2),
   PRIMARY KEY (ID)
);

Here, we are inserting some records into the above-created table using the query below −


INSERT INTO CUSTOMERS VALUES 
(1, ''Ramesh'', ''32'', ''Ahmedabad'', 2000),
(2, ''Khilan'', ''25'', ''Delhi'', 1500),
(3, ''Kaushik'', ''23'', ''Kota'', 2500),
(4, ''Chaitali'', ''26'', ''Mumbai'', 6500),
(5, ''Hardik'',''27'', ''Bhopal'', 8500),
(6, ''Komal'', ''22'', ''MP'', 9000),
(7, ''Muffy'', ''24'', ''Indore'', 5500);

Creating a view −

Now, let us create a view based on the above created table using the following query −


CREATE VIEW CUSTOMERS_VIEW AS SELECT * FROM CUSTOMERS;

The view will be created as follows −










ID NAME AGE ADDRESS SALARY
1 Ramesh 32 Ahmedabad 2000.00
2 Khilan 25 Delhi 1500.00
3 Kaushik 23 Kota 2000.00
4 Chaitali 25 Mumbai 6500.00
5 Hardik 27 Bhopal 8500.00
6 Komal 22 Hyderabad 4500.00
7 Muffy 24 Indore 10000.00

Renaming the view −

Now, we know that we are having an existing view in our database named “CUSTOMERS_VIEW”. So, we are going to rename this view to VIEW_CUSTOMERS using the below query −


RENAME TABLE CUSTOMERS_VIEW TO VIEW_CUSTOMERS;

Verification

Using the following SELECT statement, we can verify whether the view is renamed or not −


SELECT * FROM VIEW_CUSTOMERS;

The “VIEW_CUSTOMERS” view displayed is as follows −










ID NAME AGE ADDRESS SALARY
1 Ramesh 32 Ahmedabad 2000.00
2 Khilan 25 Delhi 1500.00
3 Kaushik 23 Kota 2000.00
4 Chaitali 25 Mumbai 6500.00
5 Hardik 27 Bhopal 8500.00
6 Komal 22 Hyderabad 4500.00
7 Muffy 24 Indore 10000.00

Rules to be followed while Renaming Views

There are some rules and practices to ensure that the renaming process goes smoothly and one should follow them while renaming a view in MySQL. They are listed below:

  • Avoid renaming system views: In MySQL, the system views are views that contain all the information about the database management system. It is recommended not to rename these views because it can cause issues with the functioning of the database.

  • Update all references to the view: After renaming a view in MySQL, any stored procedures, triggers, or other database objects that reference the view will need to be updated to use the new name of the view. If we failed to update these references results in errors or issues with the functioning of the database system.

  • Test thoroughly: It is important to test the renaming process thoroughly in the development or testing environment to make sure that all references to the view have been updated correctly.

  • Use a consistent naming convention: While working with views in MySQL, it”s recommended to use a consistent naming convention. If you need to rename a view, follow the same naming convention you”ve used for other views in the database.

  • Backup the database: Before renaming a view, it is recommended to have a backup of the database to make sure that you have a restore point.


Renaming a View Using a Client Program

Until now, we used an SQL statement to rename a view directly in the MySQL database. But, we can also perform the same rename operation on a view using another client program.

Syntax

To Rename a view into MySQL Database through a PHP program, we need to execute the RENAME statement using the mysqli function named query() as follows −


$sql = "RENAME TABLE first_view To tutorial_view";
$mysqli->query($sql);

To Rename a view into MySQL Database through a JavaScript program, we need to execute the RENAME statement using the query() function of mysql2 library as follows −


sql = "RENAME TABLE CUSTOMERS_VIEW TO VIEW_CUSTOMERS";
con.query(sql);  

To Rename a view into MySQL Database through a Java program, we need to execute the RENAME statement using the JDBC function named executeQuery() as follows −


String sql = "RENAME TABLE first_view TO tutorial_view";
st.executeQuery(sql);

To Rename a view into MySQL Database through a python program, we need to execute the RENAME statement using the execute() function of the MySQL Connector/Python as follows −


rename_view_query = "RENAME TABLE tutorial_view TO new_tutorial_view"
cursorObj.execute(rename_view_query)

Example

Following are the programs −


$dbhost = ''localhost'';
$dbuser = ''root'';
$dbpass = ''password'';
$dbname = ''TUTORIALS'';
$mysqli = new mysqli($dbhost, $dbuser, $dbpass, $dbname);

if ($mysqli->connect_errno) {
    printf("Connect failed: %s
", $mysqli->connect_error); exit(); } // printf(''Connected successfully.
''); // A view can be renamed by using the RENAME TABLE old_view_name TO new_view_name $sql = "RENAME TABLE first_view To tutorial_view"; if ($mysqli->query($sql)) { printf("View renamed successfully!.
"); } if ($mysqli->errno) { printf("View could not be renamed!.
", $mysqli->error); } $mysqli->close();

Output

The output obtained is as follows −


View renamed successfully!. 


var mysql = require(''mysql2'');
var con = mysql.createConnection({
    host: "localhost",
    user: "root",
    password: "Nr5a0204@123"
});

  //Connecting to MySQL
  con.connect(function (err) {
  if (err) throw err;
  console.log("Connected!");
  console.log("--------------------------");

  sql = "create database TUTORIALS"
  con.query(sql);

  sql = "USE TUTORIALS"
  con.query(sql);

  sql = "CREATE TABLE CUSTOMERS (ID INT NOT NULL,NAME VARCHAR (20) NOT NULL,AGE INT NOT NULL,ADDRESS CHAR (25),SALARY DECIMAL (18, 2),PRIMARY KEY (ID));"
  con.query(sql);

  sql = "INSERT INTO CUSTOMERS (ID,NAME,AGE,ADDRESS,SALARY) VALUES (1, ''Ramesh'', 32, ''Ahmedabad'', 2000.00 ),(2, ''Khilan'', 25, ''Delhi'', 1500.00 ),(3, ''kaushik'', 23, ''Kota'', 2000.00 ),(4, ''Chaitali'', 25, ''Mumbai'', 6500.00 ),(5, ''Hardik'', 27, ''Bhopal'', 8500.00 ),(6, ''Komal'' ,22, ''MP'', 4500.00 ),(7, ''Muffy'', 24, ''Indore'', 10000.00 );"
  con.query(sql);

  //Creating View
  sql = "Create view CUSTOMERS_VIEW AS SELECT * FROM CUSTOMERS";
  con.query(sql);

  //Renaming View
  sql = "RENAME TABLE CUSTOMERS_VIEW TO VIEW_CUSTOMERS;"
  con.query(sql);

  //Displaying records from view
  sql = "SELECT * FROM VIEW_CUSTOMERS;"
  con.query(sql, function(err, result){
    if (err) throw err
    console.log("**Views after deleting:**");
    console.log(result);
  });

});   

Output

The output produced is as follows −


Connected!
--------------------------
[
  {ID: 1, NAME: ''Ramesh'', AGE: 32, ADDRESS: ''Ahmedabad'', SALARY: ''2000.00''},
  {ID: 2, NAME: ''Khilan'', AGE: 25, ADDRESS: ''Delhi'', SALARY: ''1500.00''},
  {ID: 3, NAME: ''kaushik'', AGE: 23, ADDRESS: ''Kota'', SALARY: ''2000.00''},
  {ID: 4, NAME: ''Chaitali'', AGE: 25, ADDRESS: ''Mumbai'', SALARY: ''6500.00''},
  {ID: 5, NAME: ''Hardik'', AGE: 27, ADDRESS: ''Bhopal'', SALARY: ''8500.00''},
  {ID: 6, NAME: ''Komal'', AGE: 22, ADDRESS: ''MP'', SALARY: ''4500.00'' },
  {ID: 7, NAME: ''Muffy'', AGE: 24, ADDRESS: ''Indore'', SALARY: ''10000.00''}
]  


import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.Statement;

public class RenameView {
   public static void main(String[] args) {
      String url = "jdbc:mysql://localhost:3306/TUTORIALS";
      String username = "root";
      String password = "password";
      try {
         Class.forName("com.mysql.cj.jdbc.Driver");
         Connection connection = DriverManager.getConnection(url, username, password);
         Statement statement = connection.createStatement();
         System.out.println("Connected successfully...!");

         //Rename Created View.....
         String sql = "RENAME TABLE first_view TO tutorial_view";
         statement.executeUpdate(sql);
         System.out.println("Renamed view Successfully...!");
         ResultSet resultSet = statement.executeQuery("SELECT * FROM tutorial_view");
         while (resultSet.next()) {
            System.out.print(resultSet.getInt(1)+" "+ resultSet.getString(2)+ " "+ resultSet.getString(3));
            System.out.println();
         }
         connection.close();
      } catch (Exception e) {
         System.out.println(e);
      }
   }
}  

Output

The output obtained is as shown below −


Connected successfully...!
Renamed view Successfully...!
1 Learn PHP John Paul  


import mysql.connector
#establishing the connection
connection = mysql.connector.connect(
    host=''localhost'',
    user=''root'',
    password=''password'',
    database=''tut''
)
cursorObj = connection.cursor()
rename_view_query = "RENAME TABLE tutorial_view TO new_tutorial_view"
cursorObj.execute(rename_view_query)
connection.commit()
print("View renamed successfully.")
cursorObj.close()
connection.close()                

Output

Following is the output of the above code −


View renamed successfully.


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