多项选择题

A. You can use aggregate functions in any clause of a S……

Which two are true about aggregate functions? （）

A. You can use aggregate functions in any clause of a SELECT statement.
B. You can use aggregate functions only in the column list of the select clause and in the WHERE clause of a SELECT statement.
C. You can mix single row columns with aggregate functions in the column list of a SELECT statement by grouping on the single row columns.
D. You can pass column names, expressions, constants, or functions as parameter to an aggregate function.
E. You can use aggregate functions on a table, only by grouping the whole table as one single group.
F. You cannot group the rows of a table by more than one column while using aggregate functions.

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单项选择题You need to perform these tasks: 1. Create and assign a MANAGER role to Blake and Clark 2. Grant CREATE TABLE and CREATE VIEW privileges to Blake and Clark Which set of SQL statements achieves the desired results?（）

A. CREATE ROLE manager; GRANT create table, create view TO manager; GRANT manager TO BLACK, CLARK;
B. CREATE ROLE manager; GRANT create table, create voew TO manager; GRANT manager ROLE TO BLACK, CLARK;
C. GRANT manager ROLE TO BLACK, CLARK; GRANT create table, create voew TO BLACK CLARK; ***MISSING***

单项选择题Which one is a system privilege?（）

A. SELECT
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E. CREATE TABLE

单项选择题Which SQL statement displays the date March 19, 2001 in a format that appears as Nineteenth of March 2001 12:00:00 AM ?（）

A. SELECT TO_CHAR(TO_DATE('19-Mar-2001', 'DD-Mon-YYYY'), 'fmDdspth "of" Month YYYY fmHH:MI:SS AM') NEW_DATE FROM dual;
B. SELECT TO_CHAR(TO_DATE('19-Mar-2001', 'DD-Mon-YYYY'), 'Ddspth "of" Month YYYY fmHH:MI:SS AM') NEW_DATE HH:MI:SS AM') NEW _ DATE FROM dual;
C. SELECT TO_CHAR(TO_DATE('19-Mar-2001', 'DD-Mon-YYYY'), 'fmDdspth "of" Month YYYY NEW _ DATE FROM dual;
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单项选择题The EMPLOYEES table contains these columns: You need to write a query that will produce these results: 1. Display the salary multiplied by the commission_pct. 2. Exclude employees with a zero commission_pct. 3. Display a zero for employees with a null commission value. Evaluate the SQL statement: What does the statement provide?（）

A. All of the desired results
B. Two of the desired results
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单项选择题A subquery can be used to（）.

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