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A record is a data structure that is a collection of ___ (elements), each with its own name and type that appear in a table as group of ___ across one row.
fields
A record is a data structure that is a collection of fields (elements), each with its own name and type that appear in a ___ as group of fields across one row.
table
Most modern database management systems implement a relational model in which the data is organized in ___ .
relations (tables)
A one-to-one relationship is an association between two tables in which the primary key value of each record in the primary table corresponds to the value in the matching field of one, and only one, record in the ___ .
related table
A ___ relationship is a complex association between two sets of parameters in which many parameters of each set can relate to many others in the second set.
many-to-many
A parent/child relationship is a relationship between nodes in a ___ in which the parent is one step closer to the root (that is, one level higher) than the child.
tree data structure
Structured query language (SQL) is ___ .
a relational database language used in querying, updating, and managing relational databases and is the de facto standard for database products
___ is used to insert, update, and delete data and to query a database.
Data manipulation language (DML)
Data definition language (DDL) is used to ___ .
create, modify, or drop relational databases, entities, attributes, and other objects (e.g. views)
Which DDL command can Raj use to add a new field to the Cycle table to store the filename of the photo? ___
ALTER TABLE Cycle ADD photo _ file _ name CHAR (30) NULL
What is the main difference between the DML command DELETE and the DDL command DROP? ___
DELETE removes all (or a subset of) records from the table only; it does not remove the table
___ is a description of a database to a database management system (DBMS) in the language provided by the DBMS.
A schema
Data definition language (DDL) defines database objects including ___ .
entities, attributes, views, and indexes
___ specify the possible range of values of the set, the operations that can be performed on the values, and the way in which the values are stored in memory.
Data type
Data types specify the possible range of values of the set, the operations that can be performed on the values, and the way in which the values are ___.
stored in memory
An identifier for a record in a data file that is unique and found in only one record is called a ___ . A Social Security number may serve as a ___ in an database of employees.
key
A graphical designer is an application, such as Microsoft Access, that is ___ .
object-oriented and drag-and-drop driven
Transact-SQL (T-SQL) is a sophisticated query language with additional features beyond what is defined in the ___ .
ANSI SQL
____ is a sophisticated query language with additional features beyond what is defined in the ANSI SQL.
Transact-SQL (T-SQL)
Graphical designers include applications such as Microsoft Access, which are ___ .
object-oriented and drag-and-drop driven
___ are compact segments of user-written SQL code that can accept parameters and return either a value or a table.
User-defined functions
Which command would ensure that return visitors are only counted once when running a query against the reservation system? ___
SELECT DISTINCT
For some of the reports it will be useful to see the results in alphabetical order. Which command will produce an alphabetical list? ___
ORDER BY column _ name (either ASC or DESC)
A truth table is helpful in visualizing the results of logical operators. When comparing two fields, which condition always results in TRUE? ___
OR operator and at least one field = TRUE
Boolean logical operators : AND displays a record if both the first condition ___ .
and the second condition are true
Boolean logical operators : OR displays a record if either the first condition ___ .
or the second conditions are true
Which statement best defines a predicate subquery?
uses extended logical constructs in the WHERE clause using AND, OR, LIKE, BETWEEN, AS, and TOP
What is the difference between UNION and JOIN?
UNION combines the results of two SQL queries when there is the same number of columns and data types; JOIN returns rows when there is at least one column match
When should the INTERSECT query be used?
To return only the rows that appear in both tables, similar to a Boolean AND
When designing the INSERT SQL, what happens if data is missing for a particular column? ___
The INSERT statement uses the default value for the column.
How can you set up the INSERT to allow copy rows from other tables? ___
You can use the INSERT INTO with a SELECT FROM clause.
The ___ statement is used to insert a new row in a table when a sub-select is used instead of the VALUES clause.
INSERT INTO with SELECT
The INSERT INTO with SELECT statement is used to insert a new row in a table when a sub-select is used instead of the ___ .
VALUES clause
To update all records in a database to reflect an increase in the provincial value-added tax from 8 percent to 10 percent the developer should use: ___
UPDATE RENTALS SET value _ added _ tax = .10
You want to update data if a condition is true and perform an alternative update if the condition is false. Which of the following is the best choice? ___
CASE statement
One of the developers mentioned that sometimes he needs to update data in one table from another table. Which of the following is the correct syntax for this type of update?
UPDATE RENTALS SET kayak = RENTALS.kayak + EQUIPMENT.kayak
FROM RENTALS, EQUIPMENT
The value of the case expression is the value of the ___ that is true. If none is true, the result is the ELSE.
first WHEN clause
The value of the case expression is the value of the first WHEN clause that is true. If none is true, the result is the ___
ELSE
What happens if a WHERE statement is not included with the DELETE statement? ___
The data from the table is deleted
How are transactions useful when updating/deleting/adding records to a database? ___
They allows multiple statements to be grouped together to avoid data integrity errors
How can a programmer enforce data integrity rules when making changes to the records in a database? ___
When all statements in a transaction have successfully completed, issue a commit statement
What is not a benefit of enforcing Second and Third Normal Forms? ___
Indexed data for easy retrieval
___ involves applying a body of techniques to a relational database to minimize the inclusion of duplicate information.
Normalization
Normal Form is the result of structuring (organizing) information to avoid ___ and to promote efficient maintenance, storage, and updating.
redundancy and inconsistency
Normal Form is the result of structuring (organizing) information to avoid redundancy and inconsistency and to promote ___ .
efficient maintenance, storage, and updating
___ is the result of structuring (organizing) information to avoid redundancy and inconsistency and to promote efficient maintenance, storage, and updating.
Normal Form
___ sets a few basic rules for a database: eliminate duplicative columns from the same table.
The First Normal Form (1NF)
___ = 1NF + removing subsets of data that apply to multiple rows of a table and place them in separate tables.
The Second Normal Form (2NF)
___ = 2NF + removing columns that are not dependent upon the primary key.
The Third Normal Form (3NF)
The First Normal Form (1NF) sets a few basic rules for a database: ___
eliminate duplicative columns from the same table.
The Second Normal Form (2NF) = 1NF + removing subsets of data that apply to multiple rows of a table and place them in ___ .
separate tables
The Third Normal Form (3NF) = 2NF + ___ that are not dependent upon the primary key.
removing columns
___ serves as the unique identifier of a specific row and uniquely defines a relationship within a database.
A primary key
A primary key serves as the ___ of a specific row and uniquely defines a relationship within a database.
unique identifier
An ___ contains keywords and associated data that point to the location of more comprehensive information, such as files and records on a disk or record keys in a database.
index
In a ___ structure for storing database indexes, each node in the tree contains a sorted list of key values and links that correspond to ranges of key values between the listed values.
b-tree
A ___ index is arranged similarly to the index of a book, where the index value points to the actual information.
non-clustered
A ___ is arranged in a special order to make retrieval of information faster with direct access to the information.
clustered index
What should be included in the physical security plan? ___
location of servers with restricted access
Roles ___ to the database. Defined roles give all users within a group the same permissions.
grant permissions
Roles grant permissions to the database. Defined roles give all users within a group the same ___ .
permissions
Replication services are recommended when: ___
The database must be available 24 hours a day, 7 days a week
___ is a process of saving all critical data to re-create the database in useful form in a relatively short
Backup
In a ___ backup only files that have been changed since the last full_backup are copied.
differential