[August 2019] original question of OCP 071 Certification examination-question 35
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.)
