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An M:N table, also known as a many-to-many, link, or bridge table, primarily
contains foreign keys. ---------CORRECT ANSWER-----------------false
-This new M:N table is often called a bridge table, junction table, or link table
-When an M:N relationship is non-identifying, by definition the primary keys
(foreign keys that reference the primary keys of the M:N referenced tables) are
not part of the M:N relationship
Referential integrity requires every non-null foreign key value must reference an
existing primary key value. ---------CORRECT ANSWER-----------------true
-foreign key cannot be null
The SQL statement contains a subquery. ---------CORRECT ANSWER-----------------
true
-A subquery is a query (SELECT statement) inside another query
-A subquery is normally expressed inside parentheses
The SQL statement contains a LEFT OUTER JOIN. ---------CORRECT ANSWER----------
-------false
,-LEFT: all rows from left table and matching joined rows/values
SELECT column-list
FROM table1 LEFT [OUTER] JOIN table2 ON join-condition
The SQL statement contains a correlated subquery. ---------CORRECT ANSWER------
-----------false
-A subquery that may be executed independent of the outer query is called an
uncorrelated subquery
-A subquery that references the outer query is called a correlated subquery
An index should be added for column Name of table haircuts. ---------CORRECT
ANSWER-----------------false
-Indexes are an ordered arrangement of keys and pointers to efficiently access
and retrieve data
-Relational database indexes are similar to using an index in a text book to find a
page number for a topic
-An index key is the reference point in an index and points to a location of the
data identified by the key
-An index may provide an orderly arrangement to logically access table rows
-Each index in an RDBMS is associated with only one table, although a table may
have more than one index
-Index keys may be composed of one or more attributes
, A MySQL database column will only enforce uniqueness if the column is a primary
key. ---------CORRECT ANSWER-----------------false
-Primary keys automatically use a unique index on the primary key column(s)
-a unique index only allows a single pointer value (row) for each index key
-Using a surrogate key does not remove the need to maintain uniqueness of the
natural key
-A unique index is applied to a natural key to ensure unique natural key values
-A unique index by default does not preclude NULL values, and in fact will allow
multiple NULL values
The ACID model is a set of database design principles emphasizing reliability. ------
---CORRECT ANSWER-----------------true
-The ACID model is a set of database design principles that emphasize aspects of
reliability that are important for business data and mission-critical applications
The acronym CRUD represents the four basic functions of persistence storage. ----
-----CORRECT ANSWER-----------------true
-In computer programming, create, read, update, and delete[1] (CRUD) are the
four basic functions of persistent storage.
When modeling a database from a website, web pages become database entities
---------CORRECT ANSWER-----------------false
-HTTP is the primary protocol used in web-based communication