DB CH2
A relational database is a collection of tables.
True
In relational database shorthand, the structure of a relational database is written with the name of the table followed by the columns in the table listed within parentheses.
True
In the Access Query window, the upper portion of the window contains the design grid.
True
In a relation, the order of rows is important.
False
The attributes of an entity become the fields or columns in a table.
True
Which of the following is true if two tables have the same number of columns and their corresponding columns represent the same type of data? a. They are union compatible. b. They are intersection compatible. c. They are difference compatible. d. They are product compatible.
a. They are union compatible.
Which command creates a table containing all rows that are in either or both of two tables? a. UNION b. SUBTRACT c. JOIN d. INTERSECT
a. UNION
Which of the following is the column or collection of columns that uniquely identifies a given row in that table? a. primary key b. secondary key c. foreign key d. minor key
a. primary key
Which of the following is NOT true about a relation in a two-dimensional table? a. The entries in the table are single-valued. b. All values in a column are values of the same attribute. c. Two or more columns can share the same name. d. The order of rows is immaterial.
c. Two or more columns can share the same name.
The relationships between tables are implemented through common ____________________.
columns
Which command contains all rows that are common in two tables? a. UNION b. SUBTRACT c. JOIN d. INTERSECT
d. INTERSECT
Which operation will allow you to extract data from more than one table? a. Select b. Merge c. Project d. Join
d. Join
A relational database handles entities, attributes, and relationships by storing each entity in its own row.
false
A query ___________________ is a DBMS component that analyzes queries and attempts to determine the most efficient way to execute a given query.
optimizer
To list the records in a query's results in a particular order, you need to ____________________ the records
sort
A ____________________ query in Access allows you to enter criterion when you run the query, as opposed to placing it in the design grid.
parameter
A(n) ____________________ database is a collection of tables.
relational
Multiple entries in tables are often called ____________________.
repeating groups
Which operation is performed by the SUBTRACT command in relational algebra? a. union b. difference c. product d. intersection
b. difference
What type of query creates a new table using the query results? a. new-table b. make-table c. create-table d. merge-table
b. make-table
When some of the entries in a structure contain repeating groups and thus are not single-valued, the structure is called a(n) ____________________.
unnormalized relation
A(n) ______________ query makes a specified change to all records satisfying the criteria in the query.
update
When both criteria must be true for the compound criterion to be true, the _______________ operator is being used.
AND
The concept of grouping means that statistics will be calculated for individual records.
False
To select data from more than one table at the same time, you need to perform a make-table query.
False
A query is a question represented in a way that the DBMS can recognize and process.
True
What type of query changes data? a. addition b. update c. update d. select
c. update
In relational algebra, what command causes only certain columns to be included in the new table? a. SELECT b. DELETE c. PROGRAM d. PROJECT
d. PROJECT
If you are sorting records by more than one field, which field is the more important field? a. primary sort key b. secondary sort key c. maximum sort key d. minor sort key
a. primary sort key
Based on the table below, which command creates a new table named CustState containing the fields CustomerNum and State? Customer (CustomerNum, CustomerName, Street, City, State, PostalCode) a. JOIN Customer WITH (CustomerNum, State) GIVING CustState b. PROJECT Customer OVER (CustomerNum, State) GIVING CustState c. SELECT Customer OVER (CustomerNum, State) GIVING CustState d. MAKE-TABLE CustState FROM Customer WITH (CustomerNum, State)
b. PROJECT Customer OVER (CustomerNum, State) GIVING CustState
Based on the table below, which command lists all information from the table concerning the customer with CustomerNum 260? Customer (CustomerNum, CustomerName, Street, City, State, PostalCode) a. SELECT Customer 260 RESULTS Answer b. SELECT Customer WHERE CustomerNum=260 GIVING Answer c. SELECT Customer GIVING Answer WHERE CustomerNum='260' d. SELECT Customer WHERE CustomerNum='260' RESULTS Answer
b. SELECT Customer WHERE CustomerNum=260 GIVING Answer
How do you refer to a column named State in a table named Client? a. State.Client b. State(Client) c. Client.State d. Client(State)
c. Client.State
What uniquely identifies a row in a table? a. attribute b. column c. primary key d. field
c. primary key
Which operator is used to concatenate every row in the first table with every row in the second table? a. union b. difference c. product d. intersection
c. product
A ______________ primary key is composed of more than one column so that the row is unique.
composite
Based on the tables below, which command creates a new table named CustSales that combines the Customer and SalesPerson tables based on SalesPersonNum? Customer (CustomerNum, CustomerName, Street, City, State, PostalCode, SalesPersonNum) SalesPerson (SalesPersonNum, LastName, FirstName) a. PROJECT Customer SalesPerson WHERE Customer.SalesPersonNum=SalesPerson.SalesPersonNum MAKING CustSales b. UNION Customer SalesPerson WHERE Customer.SalesPersonNum=SalesPerson.SalesPersonNum MAKING CustSales c. SELECT Customer SalesPerson JOIN Customer.SalesPersonNum=SalesPerson.SalesPersonNum GIVING CustSales d. JOIN Customer SalesPerson WHERE Customer.SalesPersonNum=SalesPerson.SalesPersonNum GIVING CustSales
d. JOIN Customer SalesPerson WHERE Customer.SalesPersonNum=SalesPerson.SalesPersonNum GIVING CustSales
What type of functions are Count, Sum, Avg, Max, and Min? a. accumulation b. allowed c. primary d. aggregate
d. aggregate
A column whose value uniquely identifies a given row in the table is the secondary key.
False
In an AND criterion, the overall criterion is true if either of the individual criteria is true.
False
The field on which records are sorted is called the composite primary key.
False
The primary key of a table is the row or rows that uniquely identify a given column in that table.
False
The relational operators are +, *, %, and /.
False
In Access, a parameter query allows you to enter criterion when you run the query.
True
The compound criteria (conditions) are created by using which of the following two keywords? a. AND, OR b. AND, NOR c. OR, NOT d. NOT, ONLY
a. AND, OR
Which term is another word for a row in a table? a. tuple b. field c. group d. relation
a. tuple