A. UNIQUE B. COUNT C. DISTINCT D. UNION
A. SUM(COLUMN NAME) B. MAX(COLUMN NAME) C. AVG(COLUMN NAME) D. COUNT(*)
AGE IS NULL B. AGE IS NOT NULL C. AGE=NULL D. NOT(AGE IS NULL)
A. '_ _W _%' B. '_ W _ %' C. '_ W _ _' D. ' _ %W _ _'
A. SELECT B. SELECT，FROM C. SELECT，GROUP D. SELECT，INTO
A. S.S B. = SC.S C. and C.C D. = SC.C E. and SEX=’M’ and CNAME=’DATABASE’ F. S.S G. = SC.S H. and C.C I. = SC.C J. and SEX in’M’and CNAME in’DATABASE’ K. SEX ’M’ and CNAME ’ DATABASE’ L. S.SEX=’M’ and CNAME=’ DATABASE’
A. S B. SC，C C. S，SC D. S，C，SC
A. DELETE B. DROP CLEAR D. REMORE
A. YEAR() B. GETDATE() COUNT() D. SUM()
A. select right('hello',3)return value=hel B. select ltrim(rtrim(' hello '))return value=hello (without spaces) C. select replace('hello','e','o') return value=hollo D. select len('hello') return value=5
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