Answer Posted / guru

You can change the column data type using this query:

Alter table table_name modify column_name datatype(length)

For example:
Alter table user modify name char(30)
You can change column name using this query:

Alter table table_name change old_column_name
new_column_name datatype(length)

For example:
Alter table user change user user_name char(30)

If you want to change column name and data type in single
query, then you use this query:

Alter table table_name change old_column_name
new_column_name new_datatype(10)

For example:
Alter table user change name user_name char(30)

For more details visit,

http://www.phponwebsites.com/2013/12/mysql-change-column-name.html
(for change column name)

http://www.phponwebsites.com/2013/12/mysql-change-column-datatype.html(for
change column datatype)

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