sql server alter column

ALTER TABLE Customers
ADD Email varchar(255);

ALTER TABLE table_name 
ALTER COLUMN column_name new_data_type(size);

ALTER TABLE table_name
ALTER COLUMN column_name datatype;

ALTER TABLE table_name
ALTER COLUMN column_name datatype;

-- Example
ALTER TABLE product
ALTER COLUMN description VARCHAR(250);

ALTER TABLE dbo.doc_exa 
ADD column_b VARCHAR(20) NULL, 
	column_c INT NULL ;

ALTER TABLE `Table Name` MODIFY COLUMN `Column Name` Datatype(Size);

ALTER TABLE table_name

DROP COLUMN column_name; 

ALTER TABLE table_name

ADD column_name datatype; 

EXEC sp_RENAME 'table_name.oldColumn_name' , 'newColumn_name', 'COLUMN'

ALTER TABLE table_name

ALTER COLUMN column_name datatype;