若要找出关系R中B属性值包含字符'h'的所有元组，选择子句的WHERE后应表达为（）。

A.C='C1' OR C='C2' AND D>10

B.(C='C1' OR C='C2') AND D>10

C.D>10 AND C='C1' OR C='C2'

D.D>10 OR C='C1' AND C='C2'

A.Y函数依赖于X

B.Y对X完全函数依赖

C.X为U的候选码

D.R属于2NF

A.7和8

B.7和15

C.12和8

D.12和15

A.属性

B.关系

C.域

D.元组

A.HAVING

B.SELECT

C.WHERE

D.GROUP BY

A.SELECT

B.WHERE

C.FROM

D.GROUP BY

A.1NF

B.2NF

C.3NF

D.BCNF

A.1NF

B.2NF

C.3NF

D.BCNF

A.3NF

B.1NF

C.2NF

D.BCNF

A.{A, B, C, D}

B.{A, B, E, D}

C.{A, B, E, D, H}

D.{A, B, C, D, E, H, G}