SQL Server Alter Alter столбец
ALTER TABLE table_name
ALTER COLUMN column_name new_data_type(size);
Weary Wryneck
ALTER TABLE table_name
ALTER COLUMN column_name new_data_type(size);
ALTER TABLE table
ADD COLUMN column VARCHAR (255) NOT NULL AFTER column;ALTER TABLE table_name
ADD column_name datatype;ALTER TABLE table_name
ADD CONSTRAINT MyUniqueConstraint UNIQUE(column1, column2...);