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UML-style E-R diagrams allow for the existence of class attributes which are attributes
that pertain to the collection of all entities within that class, not to the individual entity
instances themselves.
To set a column value to an initial value that is selected according to some complicated
business logic, you would use the SQL DEFAULT constraint with the CREATE TABLE
command.
Requiring all application programs to lock resources in the same order is one way of
preventing a deadlock condition.
Each entity in the extended E-R model is represented as a table in the relational
database design.
Every time we break up a relation during the normalization process, we may have to
create a referential integrity constraint.
In order to create MySQL EER diagrams, users must log into MySQL using the
Connect to Database and the Connect to MySQL Server dialog boxes.
When viewing a table in the GUI tools table design window in SQL Server, the notation
that should supply the values for a surrogate key is that the Identity property of that
column is set to "Yes."
In Microsoft Visio 2013, the arrow end of the Dynamic connector object points to the
table containing the primary key.
Two or more tables are joined by giving the table names in the WHERE clause and
specifying the equality of the respective column names as a condition in the GROUP
BY clause.
Triggers that have been created in MySQL are displayed as objects in the Object
Browser of the MySQL Workbench.
Database administration is more important but less difficult in multiuser database
systems than in single-user database systems.
One of the four categories of NoSQL databases used in the text is the Graphical
database.
The SQL keyword CONSTRAINT is used to define one of several types of constraints.
Subtype entities contain, apart from the identifier, only attributes that do not appear in
the supertype.
The SQL CREATE TABLE statement is used to name a new table and describe the
table's columns.
Oracle Database provides only one method for creating an Oracle Database database.
Data modelers agree that weak, non-ID-dependent entities exist and are important.
All identifying relationships are 1:N.
The columns to be obtained by an SQL command are listed after the FROM keyword.
With SQL Server, the clustered index is faster for data retrieval.
When using a doubly nested set of NOT EXISTS SELECT statements, a row that does
not match any row matches every row.
Applet bytecode is sent to the user's computer and is invoked using the HTTP protocol.
Entities containing multivalued attributes are often represented using subtypes.
A relation is in 3NF if and only if it is in 2NF and there are no non-key attributes
determined by another non-key attribute.
A "hybrid object" is a semantic object that relates two or more objects and stores data
that are peculiar to that relationship.
Sequences are most often used to provide values for surrogate keys.
Depending on the DBMS, when changing the minimum cardinality on the parent side
from zero to one, the foreign key constraint that defines the relationship may have to be
dropped before the change is made and re-added afterwards.
Amazon.com's Dynamo was an early example of structured storage.
One example of a database design using an ID-dependent relationship is the
archetype/instance pattern.
Business Intelligence (BI) reporting systems are intended to create meaningful
information from disparate data sources and to deliver that information to the proper
users on a timely basis.
A primary key is a candidate key that has been selected to uniquely identify rows in a
relation.
ADO.NET is a completely new product, with no connection to ADO except the similar
name.
Because SQL stored procedures allow and encourage code sharing among developers,
stored procedures give database application developers the advantages of less work,
standardized processing, and specialization among developers.
In SQL Server, a transaction log backup makes a copy of the changes that have been
made since the last time a backup of the entire database was made.
SQL triggers can be used with SQL operations INSERT, UPDATE, and DELETE.
There are several difficulties with increasing cardinalities from 1:1 to 1:N, one of which
is preserving the existing relationships.
The built-in function SUM can be used with any column.
To drop a constraint, no preliminary steps are needed and we can simply use the
ALTER TABLE DROP CONSTRAINT statement.
A categorization relationship is an IS-A relationship.
To represent an N:M relationship in a relational database design, in essence it is reduced
to two 1:N relationships.
