How to reset datatype of a field on sql

Answer 1

Just to clarify,
Re-set (change/update) Or Reset (set to default value) ?
And please explain your question further, what you want to do with your table

Answer 2

Like int to char or opposite

Answer 3

Change

Answer 4

Use alter table

ALTER TABLE table_name MODIFY COLUMN col_name new_datatype

Answer 5

Thank you

Answer 6

ALTER TABLE table_name
ALTER COLUMN column_name datatype; -- SQL Server

ALTER TABLE table_name
MODIFY COLUMN column_name datatype; -- My SQL

ALTER TABLE table_name
MODIFY column_name datatype; -- ORACLE