A single row subquery can retrieve data from only one table.
A SQL query statement cannot display data from table B that is referred to in its subquery, unless table B is included in the main query's FROM clause.
A SQL query statement can display data from table B that is referred to in its subquery, without including table B in its own FROM clause.
A single row subquery can retrieve data from more than one table.
A single row subquery cannot be used in a condition where the LIKE operator is used for comparison.
A multiple-row subquery cannot be used in a condition where the LIKE operator is used for comparison.
第1题:
A. The SELECT statement is syntactically accurate.
B. The SELECT statement does not work because there is no HAVING clause.
C. The SELECT statement does not work because the column specified in the GROUP BY clause is not in the SELECT list.
D. The SELECT statement does not work because the GROUP BY clause should be in the main query and not in the subquery.
第2题:
Which two statements are true regarding views?()
第3题:
A. The main query executes with the first value returned by the subquery.
B. The main query executes with the last value returned by the subquery.
C. The main query executes with all the values returned by the subquery.
D. The main query fails because the multiple-row subquery cannot be used with the comparison operator.
E. You cannot define a multiple-row subquery in the WHERE clause of a SQL query.
第4题:
You define a multiple-row subquery in the WHERE clause of an SQL query with a comparison operator "=". What happens when the main query is executed? ()
第5题:
Which three statements about subqueries are true? ()
第6题:
Which three statements are true regarding subqueries?()
第7题:
Which two statements about subqueries are true? ()
第8题:
A.
B.
C.
D. The query fails because the subquery returns more than one row.
E. The query fails because the outer query and the inner query are using different tables.
第9题:
Which three statements about subqueries are true?()
第10题:
Which two statements are true regarding subqueries? ()