117.Which statements are true regarding the WHERE and HAVING clauses in a SELECT statement?

117.Which statements are true regarding the WHERE and HAVING clauses in a SELECT statement?

(Choose all that apply.)

A.The HAVING clause can be used with aggregate functions in subqueries.

B.The WHERE clause can be used to exclude rows after dividing them into groups.

C.The WHERE clause can be used to exclude rows before dividing them into groups.

D.The aggregate functions and columns used in the HAVING clause must be specified in the SELECT list of the query.

E.The WHERE and HAVING clauses can be used in the same statement only if they are applied to different columns in the table.

答案：AC

解析：where是分组前排除行，having是分组后排除行，b错误，

having和where中的列字段，不需要必须出现在select中，按照执行语句的顺序，select是在他们的后边执行

排除D，E