EXERCISE 14 PART 1
13) The following command would work fine: insert into budget values 121,222,111;
FALSE
14) The DROP command deletes rows from a table individually or in groups.
FALSE
16) Indexes generally slow down access speed in most RDMS.
FALSE
19) Count(*) tallies only those rows that contain a value, while Count counts all rows.
FALSE
2) DCL is used to update the database with new records.
FALSE
21) The comparison operators = and != are used to establish a range of values.
FALSE
25) 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
4) A database is maintained and queried using the data mapping language (DML).
FALSE
5) The CREATE SCHEMA DDL command is used to create a table.
FALSE
7) When creating a table, it is not important to consider foreign key—primary key mates.
FALSE
8) 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
9) The DELETE TABLE DDL command is used to remove a table from the database.
FALSE
1) Some DBMS can handle graphic data types as well as text and numbers.
TRUE
10) The ALTER TABLE command is used to change a table definition.
TRUE
11) The SQL command used to populate tables is the INSERT command.
TRUE
12) An insert command does not need to have the fields listed.
TRUE
15) In order to update data in SQL, one must inform the DBMS which relation, columns, and rows are involved.
TRUE
17) 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
18) Expressions are mathematical manipulations of data in a table that may be included as part of the SELECT statement.
TRUE
20) 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
22) If multiple Boolean operators are used in an SQL statement, NOT is evaluated first, then AND, then OR.
TRUE
23) 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
24) Adding the DISTINCT keyword to a query eliminates duplicates.
TRUE
3) A database table is defined using the data definition language (DDL).
TRUE
6) When creating tables, it's important to decide which columns will allow null values before the table is created.
TRUE