Exam 6: The Basics of Querying a Database

The GROUP BY clause can use the column positional specification like the ORDER BY clause.

One of the most common uses of the DUAL table is to get the next sequential value from an Oracle sequence object.

The ____ SQL group function counts the number of rows in a group.

Queries can be sorted in ascending or descending order,where descending is the default if ASC or DESC are not specified.

____________________ queries are used to build tree-like hierarchical output row structures from hierarchical data.

____ queries use the WHERE clause to retain or filter out unwanted rows.

The ____ set operator returns one query less the other,similar to a left outer join where only distinct rows in the first query are returned.

A(n)____________________ is a vague form of a join using IN and EXISTS operators where the results contained within the subquery are not retrieved as part of the final columns selected for the result join.

Certain types of subqueries are also known as ____ because they join without returning values from the subquery.

The ____ table is used to request data from an Oracle database,where that data is not in user application tables.

Both IN and ____________________ allow a correlation between a calling query and a subquery.

An alias can be used to refer to a column,typically in a join or a subquery.

____ pattern matches between strings;those strings are expressions.

The most commonly used indexes for an Oracle database are ____ indexes.

A(n)____ can act to apply a distinct name to multiple columns with the same name.

The ____ clause extends the GROUP BY clause by filtering on resulting grouped rows (returned by the GROUP BY clause).

NULL values sort as the lowest value by default.

____________________ or version queries allow access to data at a previous point in time.

This query finds all columns in the table: SELECT ____ FROM DBA_TABLESPACES;

BETWEEN allows multiple rows of returning subqueries.