WGU C175 Focused on Lesson 5,6 & 7 Exam
Review Questions and A Level Marking
Scheme Latest 2024/2025
Portals - correct answer in terms of business intelligence, a unified, single point of
entry for information distribution.
Relational online analytical processing (rolap) - correct answer analytical processing
functions that use relational databases and familiar relational query tools to store and
analyze multidimensional data.
Roll up - correct answer (1) to aggregate data into summarized components, that is,
higher levels of aggregation. (2) in sql, an olap extension used with the group by clause
to aggregate data by different dimensions. Rolling up the data is the exact opposite of
drilling down the data.
Slice and dice - correct answer the ability to focus on slices of a data cube (drill down
or roll up) to perform a more detailed analysis.
Sparsity - correct answer in multidimensional data analysis, a measurement of the
data density held in the data cube.
Very large databases (vldbs) - correct answer database that contains huge amounts of
data—gigabyte, terabyte, and petabyte ranges are not unusual.
Two steps to check data worthiness in a relational table with data normalization -
correct answer - ensure there are no partial functional dependencies (where an
attribute is functionally dependent on the combination of two or more other attributes)
- ensure there are no transitive dependencies
Alias - correct answer an alternative name for a column or table in a sql statement.
,Alter table - correct answer the sql command used to make changes to table structure.
When the command is followed by a keyword (add or modify), it adds a column or
changes column characteristics.
And - correct answer the sql logical operator used to link multiple conditional
expressions in a where or having clause. It requires that all conditional expressions
evaluate to true.
Avg - correct answer a sql aggregate function that outputs the mean average for a
specified column or expression.
Between - correct answer in sql, a special comparison operator used to check whether
a value is within a range of specified values.
Boolean algebra - correct answer a branch of mathematics that uses the logical
operators or, and, and not.
Cascading order sequence - correct answer a nested ordering sequence for a set of
rows, such as a list in which all last names are alphabetically ordered and, within the
last names, all first names are ordered.
Commit - correct answer the sql command that permanently writes data changes to a
database.
Count - correct answer a sql aggregate function that outputs the number of rows
containing not null values for a given column or expression, sometimes used in
conjunction with the distinct clause.
Create index - correct answer a sql command that creates indexes on the basis of a
selected attribute or attributes.
Create table - correct answer a sql command that creates a table's structures using the
characteristics and attributes given.
,Delete - correct answer a sql command that allows data rows to be deleted from a
table.
Distinct - correct answer a sql clause that produces only a list of values that are
different from one another.
Drop index - correct answer a sql command used to delete database objects such as
tables, views, indexes, and users.
Drop table - correct answer a sql command used to delete database objects such as
tables, views, indexes, and users.
Exists - correct answer in sql, a comparison operator that checks whether a subquery
returns any rows.
From - correct answer a sql clause that specifies the table or tables from which data is
to be retrieved.
Group by - correct answer a sql clause used to create frequency distributions when
combined with any of the aggregate functions in a select statement.
Having - correct answer a clause applied to the output of a group by operation to
restrict selected rows.
In - correct answer in sql, a comparison operator used to check whether a value is
among a list of specified values.
Inner query - correct answer a query that is embedded or nested inside another query.
Also known as a nested query or a subquery.
, Insert - correct answer a sql command that allows the insertion of one or more data
rows into a table.
International organization for standardization (iso) - correct answer an organization
formed to develop standards for diverse network systems.
Is null - correct answer in sql, a comparison operator used to check whether an
attribute has a value.
Like - correct answer in sql, a comparison operator used to check whether an
attribute's text value matches a specified string pattern.
Max - correct answer a sql aggregate function that yields the maximum attribute value
in a given column.
Min - correct answer a sql aggregate function that yields the minimum attribute value in
a given column.
Nested query - correct answer in sql, a query that is embedded in another query. See
subquery.
Not - correct answer a sql logical operator that negates a given predicate.
Or - correct answer the sql logical operator used to link multiple conditional
expressions in a where or having clause. It requires only one of the conditional
expressions to be true.
Order by - correct answer a sql clause that is useful for ordering the output of a select
query (for example, in ascending or descending order).
Rollback - correct answer a sql command that restores the database table contents to
the condition that existed after the last commit statement.
Review Questions and A Level Marking
Scheme Latest 2024/2025
Portals - correct answer in terms of business intelligence, a unified, single point of
entry for information distribution.
Relational online analytical processing (rolap) - correct answer analytical processing
functions that use relational databases and familiar relational query tools to store and
analyze multidimensional data.
Roll up - correct answer (1) to aggregate data into summarized components, that is,
higher levels of aggregation. (2) in sql, an olap extension used with the group by clause
to aggregate data by different dimensions. Rolling up the data is the exact opposite of
drilling down the data.
Slice and dice - correct answer the ability to focus on slices of a data cube (drill down
or roll up) to perform a more detailed analysis.
Sparsity - correct answer in multidimensional data analysis, a measurement of the
data density held in the data cube.
Very large databases (vldbs) - correct answer database that contains huge amounts of
data—gigabyte, terabyte, and petabyte ranges are not unusual.
Two steps to check data worthiness in a relational table with data normalization -
correct answer - ensure there are no partial functional dependencies (where an
attribute is functionally dependent on the combination of two or more other attributes)
- ensure there are no transitive dependencies
Alias - correct answer an alternative name for a column or table in a sql statement.
,Alter table - correct answer the sql command used to make changes to table structure.
When the command is followed by a keyword (add or modify), it adds a column or
changes column characteristics.
And - correct answer the sql logical operator used to link multiple conditional
expressions in a where or having clause. It requires that all conditional expressions
evaluate to true.
Avg - correct answer a sql aggregate function that outputs the mean average for a
specified column or expression.
Between - correct answer in sql, a special comparison operator used to check whether
a value is within a range of specified values.
Boolean algebra - correct answer a branch of mathematics that uses the logical
operators or, and, and not.
Cascading order sequence - correct answer a nested ordering sequence for a set of
rows, such as a list in which all last names are alphabetically ordered and, within the
last names, all first names are ordered.
Commit - correct answer the sql command that permanently writes data changes to a
database.
Count - correct answer a sql aggregate function that outputs the number of rows
containing not null values for a given column or expression, sometimes used in
conjunction with the distinct clause.
Create index - correct answer a sql command that creates indexes on the basis of a
selected attribute or attributes.
Create table - correct answer a sql command that creates a table's structures using the
characteristics and attributes given.
,Delete - correct answer a sql command that allows data rows to be deleted from a
table.
Distinct - correct answer a sql clause that produces only a list of values that are
different from one another.
Drop index - correct answer a sql command used to delete database objects such as
tables, views, indexes, and users.
Drop table - correct answer a sql command used to delete database objects such as
tables, views, indexes, and users.
Exists - correct answer in sql, a comparison operator that checks whether a subquery
returns any rows.
From - correct answer a sql clause that specifies the table or tables from which data is
to be retrieved.
Group by - correct answer a sql clause used to create frequency distributions when
combined with any of the aggregate functions in a select statement.
Having - correct answer a clause applied to the output of a group by operation to
restrict selected rows.
In - correct answer in sql, a comparison operator used to check whether a value is
among a list of specified values.
Inner query - correct answer a query that is embedded or nested inside another query.
Also known as a nested query or a subquery.
, Insert - correct answer a sql command that allows the insertion of one or more data
rows into a table.
International organization for standardization (iso) - correct answer an organization
formed to develop standards for diverse network systems.
Is null - correct answer in sql, a comparison operator used to check whether an
attribute has a value.
Like - correct answer in sql, a comparison operator used to check whether an
attribute's text value matches a specified string pattern.
Max - correct answer a sql aggregate function that yields the maximum attribute value
in a given column.
Min - correct answer a sql aggregate function that yields the minimum attribute value in
a given column.
Nested query - correct answer in sql, a query that is embedded in another query. See
subquery.
Not - correct answer a sql logical operator that negates a given predicate.
Or - correct answer the sql logical operator used to link multiple conditional
expressions in a where or having clause. It requires only one of the conditional
expressions to be true.
Order by - correct answer a sql clause that is useful for ordering the output of a select
query (for example, in ascending or descending order).
Rollback - correct answer a sql command that restores the database table contents to
the condition that existed after the last commit statement.
