how to change the type of a column in mysql code example

Example 1: alter table column change data type to text mysql

ALTER TABLE tablename MODIFY columnname INTEGER;

Example 2: change data type in mysql

ALTER TABLE table_name

CHANGE COLUMN column_name column_name datatype;

Example 3: change column in mysql

#Alter is used
#alter table TableName change CurrentColumnName NewColumnName Specification(size);
alter table TableName change name firstname varchar(30);