Mysql Alter Add Multiple Columns
Mysql Alter Add Multiple Columns is used to modify the table and add multiple columns to the specified table.
Understand with Example
The Tutorial illustrate an example from 'Mysql Alter Add Multiple Columns'. To understand this example, we create a table 'employees' that include the required field name and data type. The table has a Empid as primary key.
Query to create table:-
CREATE TABLE `employees` (
->Empid int(10),
->Empname varchar(60),
->date date
->PRIMARY KEY(Empid)
->);
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Query to insert data into Table named employees:
Once the table is created, we use insert into that add the records or rows to the table .
mysql>insert into employees values(01,'Girish','2008-12-22'); Query OK, 1 row affected (0.02 sec) mysql>insert into employee1 values(02,'Komal','2008-12-23'); Query OK, 1 row affected (0.02 sec) |
Query to view data of Table named employees:
To view the detail from table employees we run the select query to see the records.
mysql> select * from employees; |
Output:-
+-------+---------+------------+ | Empid | Empname | date | +-------+---------+------------+ | 1 | Girish | 2008-12-22 | | 2 | Komal | 2008-12-23 | +-------+---------+------------+ 2 rows in set (0.00 sec) |
Query to alter Table named employees by adding multiple column named city:
The Query below given is used to modify the table 'employees' and add multiple columns to the table 'employees'.
mysql> alter table employees
-> add column city varchar(30),
-> add column email varchar(30);
Query OK, 2 rows affected (0.16 sec)
Records: 2 Duplicates: 0 Warnings: 0
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Output:
The select Query return you the records from table 'employees'.
mysql> select * from employees; +-------+---------+------------+------+-------+ | Empid | Empname | date | city | email | +-------+---------+------------+------+-------+ | 1 | Girish | 2008-12-22 | NULL | NULL | | 2 | Komal | 2008-12-23 | NULL | NULL | +-------+---------+------------+------+-------+ 2 rows in set (0.02 sec) |
