Final Chapter #6, Final Chapter #7, database

A join in which the joining condition is based on equality between values in the common columns is called a(n): A) equi-join. B) unilateral join. C) natural join. D) both A and C.

D

A new set of analytical functions added in SQL:2008 is referred to as: A) OLAF functions. B) MOLAP functions. C) average functions. D) OLAP functions.

D

A procedure is: A) stored within the database. B) given a unique name. C) called by name. D) all of the above.

D

A view may not be updated directly if it contains: A) the DISTINCT keyword. B) derived columns and expressions in the SELECT clause. C) uses the GROUP BY or HAVING clause. D) all of the above.

D

The benefits of a standardized relational language include: A) application longevity. B) reduced training costs. C) cross-system communication. D) all of the above.

D

The most commonly used form of join operation is the: A) outer join. B) union join. C) equi-join. D) natural join.

D

User-defined data types: A) can be a subclass of a standard type. B) can behave as an object. C) can have defined functions and methods. D) can have all of the above.

D

Which of the following is a purpose of the SQL standard? A) To specify syntax and semantics of SQL data definition and manipulation B) To specify minimal and complete standards, which permit different degrees of adoption in products C) To define the data structures and basic operations for SQL databases D) All of the above

D

A catalog is the structure that contains object descriptions created by a user.

False

A database is maintained and queried using the data mapping language (DML).

False

A function has only input parameters but can return multiple values.

False

A referential integrity constraint specifies that the existence of an attribute in one table depends upon the existence of a foreign key in the same or another table.

False

A routine is a named set of SQL statements that are considered when a data modification occurs.

False

A single value returned from an SQL query that includes an aggregate function is called a vector aggregate.

False

A subquery in which processing the inner query depends on data from the outer query is called a codependent query.

False

Indexes generally slow down access speed in most RDMS.

False

It is better not to have a result set identified before writing GROUP BY and HAVING clauses for a query.

False

MULTISET is similar to the table datatype.

False

Materialized views are stored on disk and are never refreshed.

False

One major disadvantage of the outer join is that information is easily lost.

False

Persistent Sorted Modules are extensions defined in SQL-99 that include the capability to create and drop modules of code stored in the database schema across user sessions.

False

SQL has been implemented only in the mainframe and midrange environments.

False

SQL originated from a project called System-S.

False

Specifying the attribute names in the SELECT statement will make it easier to find errors in queries and also correct for problems that may occur in the base system.

False

Subqueries can only be used in the WHERE clause.

False

The CREATE SCHEMA DDL command is used to create a table.

False

The comparison operators = and != are used to establish a range of values.

False

The following command would work fine: insert into budget values 121,222,111;

False

The following query totals sales in state= 'MA' for each salesperson. Select salesperson_id, sum(sales) from salesperson group by salesperson_id having state = 'MA';

False

The following query will execute without errors. select customer.customer_name, salesman.sales_quota from customer where customer.salesman_id = (select salesman_id where lname = 'SMITH');

False

The following two SQL statements will produce different results. Select last_name, first_name from customer where state = 'MA' or state = 'NY' or state = 'NJ' or state = 'NH' or state = 'CT'; Select last_name, first_name from customer where state in ('MA','NY','NJ','NH','CT');

False

The natural join is very rarely used.

False

Transaction integrity commands are not used to identify whole units of database changes that must be completed in full for the database to retain integrity.

False

User-defined functions can improve system performance because they will be processed as sets rather than individually, thus reducing system overhead.

False

Using an outer join produces this information: rows that do not have matching values in common columns are not included in the result table.

False

When a subquery is used in the FROM clause, it is called a denied table.

False

A correlated subquery is executed once for each iteration through the outer loop.

True

A database table is defined using the data definition language (DDL).

True

A join in which the joining condition is based on equality between values in the common column is called a(n) equi-join.

True

A major benefit of SQL as a standard is reduced training costs

True

A natural join is the same as an equi-join, except that it is performed over matching columns that have been defined with the same name, and one of the duplicate columns is eliminated.

True

A procedure is run by calling it by its name.

True

A transaction is the complete set of closely related update commands that must all be done, or none of them done, for the database to remain valid.

True

A trigger is a named set of SQL statements that are considered when a data modification occurs.

True

Adding the DISTINCT keyword to a query eliminates duplicates.

True

An SQL query that implements an outer join will return rows that do not have matching values in common columns

True

An insert command does not need to have the fields listed.

True

Establishing IF-THEN-ELSE logical processing within an SQL statement can now be accomplished by using the CASE keyword in a statement.

True

Figuring out what attributes you want in your query before you write the query will help with query writing.

True

If multiple Boolean operators are used in an SQL statement, NOT is evaluated first, then AND, then OR.

True

In order to update data in SQL, one must inform the DBMS which relation, columns, and rows are involved.

True

Joining tables or using a subquery may produce the same result.

True

One of the original purposes of the SQL standard was to provide a vehicle for portability of database definition and application modules between conforming DBMSs.

True

Persistent Stored Modules are extensions defined in SQL:1999 that include the capability to add and drop modules of code.

True

RDBMSs store database definition information in system-created tables which can be considered a data dictionary.

True

SQL is both an American and international standard for database access.

True

SQL statements can be included in another language, such as C or Java.

True

SQL:2008 allows one to calculate linear regressions, moving averages and correlations without moving the data outside of the database.

True

Some DBMS can handle graphic data types as well as text and numbers.

True

The ALTER TABLE command is used to change a table definition.

True

The FROM clause is the first statement processed in an SQL command.

True

The ORDER BY clause sorts the final results rows in ascending or descending order.

True

The SQL command used to populate tables is the INSERT command.

True

The UNION clause is used to combine the output from multiple queries into a single result table.

True

The WHERE clause includes the conditions for row selection within a single table or view and the conditions between tables or views for joining.

True

The WHERE clause is always processed before the GROUP BY clause when both occur in a SELECT statement.

True

The advantages of SQL-invoked routines are flexibility, efficiency, shareability and applicability.

True

The asterisk (*) wildcard designator can be used to select all fields from a table as well as in WHERE clauses when an exact match is not possible.

True

The content of dynamic views is generated when they are referenced

True

The following SQL statement is an example of a correlated subquery. select first_name, last_name, total_sales from salesman s1 where total_sales > all (select total_sales from salesman s2 where s1.salesman_id != s2.salesman_id);

True

The joining condition of an equi-join is based upon an equality.

True

The views are created by executing a CREATE VIEW SQL command.

True

Triggers have three parts: the event, the condition, and the action.

True

When EXISTS or NOT EXISTS is used in a subquery, the select list of the subquery will usually just select all columns as a placeholder because it doesn't matter which columns are returned.

True

When a GROUP BY clause is included in an SQL statement, only those columns with a single value for each group can be included.

True

When creating tables, it's important to decide which columns will allow null values before the table is created.

True

database

final

lets

go

Dynamic SQL: A) is used to generate appropriate SQL code on the fly as an application is processing. B) is quite volatile. C) is not used widely on the Internet. D) creates a less flexible application

A

Multiple values returned from an SQL query that includes an aggregate function are called: A) vector aggregates. B) scalar aggregates. C) agates. D) summations

A

The MERGE command: A) allows one to combine the INSERT and UPDATE operations. B) allows one to combine the INSERT and DELETE operations. C) joins 2 tables together. D) none of the above.

A

The UNION clause is used to: A) combine the output from multiple queries into a single result table. B) join two tables together to form one table. C) find all rows that do not match in two tables. D) none of the above.

A

The ________ DBA view shows information about all users of the database in Oracle. A) DBA_USERS B) USERS C) DBA_VIEWS D) DBA_INDEXES

A

The outer join syntax does not apply easily to a join condition of more than ________ tables. A) two B) three C) four D) any number of

A

To get all the customers from Hawaii sorted together, which of the following would be used? A) ORDER BY B) GROUP BY C) HAVING D) SORT

A

User-defined transactions can improve system performance because: A) transactions are processed as sets, reducing system overhead. B) transactions are mapped to SQL statements. C) speed is improved due to query optimization. D) all of the above.

A

What does the following SQL command do? insert into Customer_T values (001,'John Smith','231 West St','Boston','MA','02115'); A) Adds a new record to the Customer_T B) Creates the Customer_T table C) Deletes the Customer_T table D) Updates the Customer_T table

A

What does the following SQL statement do? Select * From Customer Where Cust_Type = "Best" A) Selects all the fields from the Customer table for each row with a customer labeled "Best" B) Selects the "*" field from the Customer table for each row with a customer labeled "Best" C) Selects fields with a "*" in them from the Customer table D) Selects all the fields from the Customer table for each row with a customer labeled "*"

A

What results will be produced by the following SQL query? Select sum(standard_price) as Total_Price from Product_V where Product_Type = 'WOOD'; A) The total price of all products that are of type wood B) The total price of all products C) The Standard_Price of the first wood product in the table D) The Standard_Price of any wood product in the table

A

What will be returned when the following SQL query is executed? Select driver_no, count(*) as num_deliveries from deliveries group by driver_no having count(*) > 2; A) A listing of all drivers who made more than 2 deliveries as well as a count of the number of deliveries B) A listing of all drivers C) A listing of the number of deliveries greater than 2 D) A listing of all drivers who made more than 2 deliveries

A

Which of the following counts ONLY rows that contain a value? A) Count B) Count(*) C) Tally(*) D) Checknum

A

________ is a set of commands used to update and query a database. A) DML B) DDL C) DCL D) DPL

A

________ use the result of the outer query to determine the processing of the inner query. A) Correlated subqueries B) Outer subqueries C) Inner subqueries D) Subqueries

A

A ________ is a temporary table used in the FROM clause of an SQL query. A) correlated subquery B) derived table C) view table D) none of the above

B

A ________ view is materialized when referenced. A) virtual B) dynamic C) materialized D) base

B

A join operation: A) brings together data from two different fields. B) causes two tables with a common domain to be combined into a single table or view. C) causes two disparate tables to be combined into a single table or view. D) is used to combine indexing operations.

B

A join that is based upon equality between values in two common columns with the same name and where one duplicate column has been removed is called a(n): A) equi-join. B) natural join. C) multivariate join. D) inner join

B

A single value returned from an SQL query that includes an aggregate function is called a(n): A) agate. B) scalar aggregate. C) vector aggregate. D) summation.

B

A type of join where a table is joined to itself is called a(n): A) unary join. B) self-join. C) unnatural join. D) pinned join.

B

A type of query that is placed within a WHERE or HAVING clause of another query is called a: A) master query. B) subquery. C) superquery. D) multi-query

B

All of the following are guidelines for better query design EXCEPT: A) understand how indexes are used in query processing. B) use a lot of self-joins. C) write simple queries. D) retrieve on the data that you need.

B

All of the following are new data types added in SQL:200n EXCEPT: A) BIGINT. B) BIT. C) MULTISET. D) XML.

B

Any create command may be reversed by using a ________ command. A) truncate B) drop C) delete D) unpack

B

DDL is typically used during which phases of the development process? A) Implementation B) Physical design C) Analysis D) All of the above

B

Explicit commands to manage transactions are needed when: A) a transaction consists of just one SQL command. B) multiple SQL commands must be run as part of a transaction. C) autocommit is set to off. D) none of the above

B

Extensions defined in SQL-99 that include the capability to create and drop modules of code stored in the database schema across user sessions are called: A) stored procedures. B) Persistent Stored Modules. C) flow control modules. D) none of the above.

B

Given a table named store with 5 fields: store_id, address, city, state, zipcode, why would the following insert command not work? insert into store values ('234 Park Street') A) It would work just fine. B) You must specify the fields to insert if you are only inserting some of the fields. C) There is no table keyword. D) None of the above.

B

In order for two queries to be UNION-compatible, they must: A) both have the same number of lines in their SQL statements. B) both output compatible data types for each column and return the same number of rows. C) both return at least one row. D) all of the above.

B

In order to embed SQL inside of another language, the ________ statement must be placed before the SQL in the host language. A) GET SQL B) EXEC SQL C) RUN SQL D) SQL SQL

B

One major advantage of the outer join is that: A) information is easily accessible. B) information is not lost. C) the query is easier to write. D) all of the above.

B

The SQL command ________ adds one or more new columns to a table. A) create table B) alter table C) create view D) create relationship

B

The ________ is the structure that contains descriptions of objects such as tables and views created by users. A) SQL B) schema C) catalog D) master view

B

The first in a series of steps to follow when creating a table is to: A) identify columns that must be unique. B) identify each attribute and its characteristics. C) create an index. D) identify columns that must be null

B

What result will the following SQL statement produce? Select Avg(standard_price) as average from Product_V; A) The average of all products in Product_V B) The average Standard_Price of all products in Product_V C) The average price of all products D) None of the above

B

What results would the following SQL statement produce? select owner, table_name from dba_tables where table_name = 'CUSTOMER'; A) A listing of all customers in the customer table B) A listing of the owner of the customer table C) A listing of the owner of the customer table as well as customers D) An error message

B

What will be returned when the following SQL statement is executed? Select driver_no, count(*) as num_deliveries from deliveries where state = 'MA' group by driver_no; A) A listing of all drivers who made deliveries to state = 'MA', sorted by driver number B) A listing of each driver who made deliveries to state = 'MA' as well as the number of deliveries that each driver has made to that state C) A count of all of the deliveries made to state = 'MA' by all drivers D) None of the above

B

What will be returned when the following SQL statement is executed? Select driver_no,count(*) as num_deliveries from deliveries group by driver_no; A) A listing of all drivers, sorted by driver number B) A listing of each driver as well as the number of deliveries that he or she has made C) A count of all of the deliveries made by all drivers D) None of the above

B

Which of the following can produce scalar and vector aggregates? A) ORDER BY B) GROUP BY C) HAVING D) SORT

B

Which of the following is a technique for optimizing the internal performance of the relational data model? A) Avoiding indexes on secondary keys B) Clustering data C) Not reporting statistics to save machine resources D) Using random index organizations

B

Which of the following is the wildcard operator in SQL statements? A) < > B) * C) = D) &

B

) In which of the following situations would one have to use an outer join in order to obtain the desired results? A) A report is desired that lists all customers who placed an order. B) A report is desired that lists all customers and the total of their orders. C) A report is desired that lists all customers, the total of their orders during the most recent month, and includes customers who did not place an order during the month (their total will be zero). D) There is never a situation that requires only an outer join.

C

A join in which rows that do not have matching values in common columns are still included in the result table is called a(n): A) natural join. B) equi-join. C) outer join. D) union join.

C

A named set of SQL statements that are considered when a data modification occurs are called: A) stored procedures. B) treatments. C) triggers. D) trapdoors.

C

All of the following are part of the coding structure for triggers EXCEPT: A) event. B) condition. C) selection. D) action.

C

EXISTS will take a value of ________ if the subquery returns an intermediate results table which contains one or more rows. A) FALSE B) 1 C) TRUE D) undefined

C

RANK and DENSE-RANK are examples of: A) ceilings. B) door functions. C) window functions. D) moving functions.

C

SQL-invoked routines can be: A) procedures. B) functions. C) all of the above. D) none of the above.

C

The command for creating a database is: A) create table. B) create view. C) create schema. D) create authorization.

C

What does the following SQL statement do? Alter Table Customer_T Add (Type Varchar (2)); A) Alters the Customer_T table to accept Type 2 Varchars B) Alters the Customer_T table to be a Type 2 Varchar C) Alters the Customer_T table, and adds a field called "Type" D) Alters the Customer_T table by adding a 2-byte field called "Varchar"

C

What result set will the following query return? Select Item_No, description from item where weight > 100 and weight < 200; A) The Item_No and description for all items weighing less than 100 B) The Item_No for all items weighing between 101 and 199 C) The Item_No and description for all items weighing between 101 and 199 D) The Item_No for all items weighing more than 200

C

Which of the following finds all groups meeting stated conditions? A) Select B) Where C) Having D) Find

C

________ differs from array because it can contain duplicates. A) BIGINT B) XML C) MULTISET D) TABLE

C

________ is a set of commands used to control a database, which includes security. A) DML B) DDL C) DCL D) DPL

C

________ takes a value of true if a subquery returns an intermediate results table which contains one or more rows. A) IN B) HAVING C) EXISTS D) EXTENTS

C

Embedded SQL consists of: A) hard-coded SQL statements included in a program written in another language. B) SQL encapsulated inside of other SQL statements. C) SQL written into a front-end application. D) SQL translated to a lower-level language.

A

In SQL, a(n) ________ subquery is a type of subquery in which processing the inner query depends on data from the outer query. A) correlated B) paired C) natural D) inner

A

What does the following SQL statement do? Delete from Customer_T where state = 'HI'; A) Deletes all records from customer_t where the state is equal to HI B) Removes the Customer_T table from the database C) Deletes all records from the Customer_T table D) None of the above

A

To eliminate duplicate rows in a query, the ________ qualifier is used in the SQL Select command. A) alter B) distinct C) check D) specific

B

What does the following SQL statement do? Update Product_T Set Unit_Price = 775 Where Product_ID = 7 A) Changes the price of a unit called Product_T to 7 B) Changes the unit price of Product 7 to 775 C) Changes the length of the Unit_Price field to 775 D) Updates the Product_T table to have a unit price of 775

B

What result set is returned from the following query? Select Customer_Name, telephone from customers where city in ('Boston','New York','Denver'); A) The Customer_Name and telephone of all customers B) The Customer_Name and telephone of all customers living in either Boston, New York or Denver C) The Customer_Name and telephone of all customers living in Boston and New York and Denver D) The Customer_Name of all customers living in Boston, New York or Denver

B

Which of the following questions is answered by the SQL statement? Select Count (Product_Description) from Product_T; A) How many products are in the table Product_T? B) How many products have product descriptions in the Product Table? C) How many characters are in the field name "Product_Description"? D) How many different columns named "Product_Description" are there in table Product_T?

B

Which of the following will produce the minimum of all standard prices? A) Select standard_price from Product_V where Standard_Price = min; B) Select min(standard_price) from Product_V; C) Select Standard_Price from min(Product_V); D) Select min(Standard_Price) from Product_V where Standard_Price = min(Standard_Price);

B

While triggers run automatically, ________ do not and have to be called. A) trapdoors B) routines C) selects D) updates

B

An interactive command that can be used to dynamically control a user session for appropriate integrity measures is: A) rollback. B) rollforward. C) set autocommit. D) expunge.

C

Establishing IF-THEN-ELSE logical processing within an SQL statement can be accomplished by: A) using the if-then-else construct. B) using the immediate if statement. C) using the CASE keyword in a statement. D) using a subquery.

C

In an SQL statement, which of the following parts states the conditions for row selection? A) Select B) From C) Where D) Group By

C

Indexes are created in most RDBMSs to: A) provide a quicker way to store data. B) decrease the amount of disk space utilized. C) provide rapid random and sequential access to base-table data. D) increase the cost of implementation

C

SQL provides the ________ technique, which involves placing an inner query within the WHERE or HAVING clause of an outer query. A) grouping B) joining C) subquery D) union

C

The SQL command ________ defines a logical table from one or more tables or views. A) create table B) alter table C) create view D) create relationship

C

What will result from the following SQL Select statement? Select min(Product_Description) from Product_V; A) The minimum value of Product_Description will be displayed. B) An error message will be generated. C) The first product description alphabetically in Product_V will be shown. D) None of the above

C

Which of the following is true of the order in which SQL statements are evaluated? A) The SELECT clause is always processed first. B) The SELECT clause is always processed last. C) The SELECT clause is processed before the ORDER BY clause. D) The GROUP BY clause is processed before the WHERE clause

C

All of the following are advantages of SQL-invoked routines EXCEPT: A) flexibility. B) efficiency. C) sharability. D) security.

D

An operation to join a table to itself is called a: A) sufficient-join. B) inner join. C) outer join. D) self-join.

D

If the DBA wishes to describe all tables in the database, which data dictionary view should be accessed in Oracle? A) dba_tab_privs B) dba_tab_comments C) dba_table_label D) dba_tables

D

The ________ clause is used to combine the output from multiple queries into a single result table. A) INTERSECT B) DIVIDE C) COLLATE D) UNION

D

What result set will the following query return? Select Item_No from Order_V where quantity > 10; A) The Item_No of all orders that had more than 10 items B) The Order_Id of all orders that had more than one item C) The Order_Id of all orders that had more than 10 items D) The Item_No of all orders that had 10 or more items

D

An equi-join is a join in which one of the duplicate columns is eliminated in the result table.

False

Combining a table with itself results in a faster query.

False

Count(*) tallies only those rows that contain a value, while Count counts all rows.

False

DBA_USERS contains comments on all tables in an Oracle database.

False

DCL is used to update the database with new records.

False

EXISTS takes a value of false if the subquery returns an intermediate result set.

False

IF-THEN-ELSE logical processing cannot be accomplished within an SQL statement.

False

Implementation of a standard can never stifle creativity and innovation.

False

The DELETE TABLE DDL command is used to remove a table from the database.

False

The DROP command deletes rows from a table individually or in groups.

False

The HAVING clause and the WHERE clause perform the same operation.

False

The ORDER BY clause is the first statement processed in an SQL command.

False

There is a special operation in SQL to join a table to itself.

False

Triggers can be used to ensure referential integrity, enforce business rules, create audit trails, replicate tables, but cannot call other triggers.

False

When creating a table, it is not important to consider foreign key—primary key mates.

False

When the SELECT clause in the create view statement contains the keyword DISTINCT, the view can be used to update data.

False

) The following two SQL statements will produce the same results. Select last_name, first_name from customer where credit_limit > 99 and credit_limit < 10001; Select last_name, first_name from customer where credit_limit between 100 and 10000;

True

Applications can be moved from one machine to another when each machine uses SQL

True

Constraints are a special case of triggers.

True

Correlated subqueries are less efficient than queries that do not use nesting.

True

Expressions are mathematical manipulations of data in a table that may be included as part of the SELECT statement.

True

In order to find out what customers have not placed an order for a particular item, one might use the NOT qualifier along with the IN qualifier.

True

The following queries produce the same results. select customer_name, customer_city from customer, salesman where customer.salesman_id = salesman.salesman_id and salesman.lname = 'SMITH'; select customer_name, customer_city from customer where customer.salesman_id = (select salesman_id from salesman where lname = 'SMITH');

True

The following query totals sales for each salesperson. Select salesperson_id, sum(sales) from salesperson group by salesperson_id;

True