CIS 3050 Chapter 7

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29) 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

3) 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

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

B

37) 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

7) 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

9) 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

2) 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) uni-lateral join. C) natural join. D) both A and C.

D

21) 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

23) 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

24) A new set of analytical functions added in SQL 200n are referred to as A) OLAF Functions. B) MOLAP Functions. C) Average Functions. D) OLAP Functions.

D

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

D

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

D

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

D

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

FALSE

41) The natural join is very rarely used. Answer

FALSE

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

FALSE

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

FALSE

47) 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') Answer

FALSE

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

FALSE

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

FALSE

54) Subqueries can only be used in the WHERE clause. Answer

FALSE

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

FALSE

58) It is better not to have a result set identified before writing group by and having clauses for a query. Answer

FALSE

59) 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. Answer

FALSE

61) Combining a table with itself results in a faster query. Answer

FALSE

63) 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. Answer

FALSE

65) DBA_USERS contains comments on all tables in an Oracle database. Answer

FALSE

67) MULTISET is similar to the table datatype. Answer

FALSE

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

FALSE

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

FALSE

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

FALSE

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

TRUE

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

TRUE

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

TRUE

46) 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') Answer

TRUE

48) 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. Answer

TRUE

50) 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. Answer

TRUE

52) 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) Answer

TRUE

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

TRUE

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

TRUE

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

TRUE

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

TRUE

62) 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. Answer

TRUE

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

TRUE

66) SQL 200n allows one to calculate linear regressions, moving averages and correlations without moving the data outside of the database. Answer

TRUE

68) Persistent stored modules are extensions defined in SQL 1999 that include the capability to add and drop modules of code. Answer

TRUE

70) Constraints are a special case of triggers. Answer

TRUE

72) Triggers have three parts the event, the condition, and the action. Answer

TRUE

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

TRUE

75) A procedure is run by calling it by its name. Answer

TRUE

12) 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

14) 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

19) 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

28) 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

36) 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

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

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

B

1) 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

10) 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

13) 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

15) 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

17) 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

18) 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

22) 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

11) ________ 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

16) 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

20) 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

25) RANK and DENSE-RANK are examples of A) Ceilings. B) Door Functions. C) Window Functions. D) Moving Functions.

C

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

C

30) 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

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

C

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

C

5) 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

6) 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

8) A type of join implemented in SQL-1999 and by extension SQL-2003 that returns all of the data from each table that is joined is called a(n) A) outer join. B) inner join. C) union join. D) intersect join.

C


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