I want to change the data type of multiple columns from float to int. What is the simplest way to do this?
There is no data to worry about, yet.
I want to change the data type of multiple columns from float to int. What is the simplest way to do this?
There is no data to worry about, yet.
To change column data type there are change method and modify method
ALTER TABLE student_info CHANGE roll_no roll_no VARCHAR(255);
ALTER TABLE student_info MODIFY roll_no VARCHAR(255);
To change the field name also use the change method
ALTER TABLE student_info CHANGE roll_no identity_no VARCHAR(255);
https://dev.mysql.com/doc/refman/8.0/en/alter-table.html
You can also set a default value for the column just add the DEFAULT keyword followed by the value.
ALTER TABLE [table_name] MODIFY [column_name] [NEW DATA TYPE] DEFAULT [VALUE];
This is also working for MariaDB (tested version 10.2)
If you want to alter the column details, set default value and add a comment, use this
ALTER TABLE [table_name] MODIFY [column_name] [new data type]
DEFAULT [VALUE] COMMENT '[column comment]'