Shulou(Shulou.com)06/01 Report--

Choose two

Which two statenents are tue about the COUNT function?

A) It can only be used for NUMBER data types.

B) COUNT (DISTINCT inv_amt) returns the number of rows excluding rows containing dupicates and NULLs in the INV_AMT column

C) COUNT (*) returns the number of rows in a table including duplicate rows and rows containing NULLs in any column.

D) A SELECT statement using the COUNT function with a DISTINCT keyword cannot have a WHERE clause.

E) COUNT (inv_amt) returns the number of rows in a table including rows with NULL in the INV_AMT column.

Answer::BC

(parsing: count ignores null values; it can be used with where.)

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