How to rearrange MySQL columns?

MySQLMySQLi Database

To rearrange the MySQL columns, check the column arrangement with the help of show create command. The syntax is as follows −

show create table yourTableName;

The syntax to rearrange the MySQL columns is as follows −

alter table yourTableName change column yourColumnName yourColumnName dataType first

For the same purpose, you can use the after keyword. The syntax is as follows −

alter table yourTableName change column yourColumnName yourColumnName dataType after yourSpecificColumnName;

Let us first check the column arrangement for the already created table “AddColumn” −

mysql> show create table AddColumn;

The following is the output −

+-----------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| Table     | Create Table                                                                                                                                                                    |
+-----------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| AddColumn | CREATE TABLE `addcolumn` (`StudentId` varchar(50) DEFAULT NULL, `StudentName` varchar(300) DEFAULT NULL ) ENGINE = InnoDB DEFAULT CHARSET = utf8mb4 COLLATE = utf8mb4_0900_ai_ci|
+-----------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
1 row in set (0.00 sec)

Now you can rearrange the StudentName column before StudentId. The query is as follows −

mysql> alter table AddColumn change StudentName StudentName varchar(300) first;
Query OK, 0 rows affected (1.28 sec)
Records: 0 Duplicates: 0 Warnings: 0

Here is the query that can be used to check the StudentName is first column or not −

mysql> desc AddColumn;

The following is the output displaying that the columns are successfully rearranged −

+-------------+--------------+------+-----+---------+-------+
| Field       | Type         | Null | Key | Default | Extra |
+-------------+--------------+------+-----+---------+-------+
| StudentName | varchar(300) | YES  |     | NULL    |       |
| StudentId   | varchar(50)  | YES  |     | NULL    |       |
+-------------+--------------+------+-----+---------+-------+
2 rows in set (0.00 sec)
raja
Published on 11-Jan-2019 08:24:14
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