SQL Cheat Sheet :: Data Definition Language

ALTER TABLE table-name ADD column-name
    { type_name [ ( prec [, scale] ) ] [COLLATE <collation name> ]
    [ NULL | NOT NULL ] }

alter table t_friend_relation rename column friend_ui to friend_uid;

ALTER TABLE table-name ALTER COLUMN column-name
    { type_name [ ( prec [, scale] ) ] [COLLATE <collation name> ]
    [ NULL | NOT NULL ] | {ADD | DROP} ROWGUIDCOL }