Ch. 6 T/F

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46) 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

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

TRUE

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

TRUE

74) Adding the DISTINCT keyword to a query eliminates duplicates.

TRUE

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

TRUE

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

FALSE

45) SQL originated from a project called System-S.

FALSE

48) Implementation of a standard can never stifle creativity and innovation.

FALSE

52) DCL is used to update the database with new records.

FALSE

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

TRUE

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

TRUE

insert into budget values 121,222,111;

FALSE

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

FALSE

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

FALSE

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

FALSE

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

FALSE

58) 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

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

FALSE

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

FALSE

66) Indexes generally slow down access speed in most RDMS.

FALSE

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

FALSE

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

FALSE

75) 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

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

FALSE

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

FALSE

81) 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

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

FALSE

86) Materialized views are stored on disk and are never refreshed.

FALSE

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

FALSE

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

TRUE

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

TRUE

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

TRUE

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

TRUE

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

TRUE

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

TRUE

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

TRUE

67) 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

70) 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

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

TRUE

73) 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

78) 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

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

TRUE

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

TRUE

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

TRUE

85) The content of dynamic views is generated when they are referenced.

TRUE

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

TRUE


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