{"id":125946,"date":"2023-11-24T04:35:23","date_gmt":"2023-11-24T04:35:23","guid":{"rendered":"https:\/\/learnexams.com\/blog\/?p=125946"},"modified":"2023-11-24T04:35:24","modified_gmt":"2023-11-24T04:35:24","slug":"d426-data-management-foundations-oa-exam-2023-2024-actual-exam-2","status":"publish","type":"post","link":"https:\/\/www.learnexams.com\/blog\/2023\/11\/24\/d426-data-management-foundations-oa-exam-2023-2024-actual-exam-2\/","title":{"rendered":"WGU C175\/D426 DATA MANAGEMENT FOUNDATIONS OAEXAM 2023-2024 ACTUAL EXAM"},"content":{"rendered":"\n

VERSION A
What does modality refer to? How does it appear on ER diagram? – ANSWER\u0002Refers to the MINIMUM number of times an instance in one entity can be
associated with instance of another entity (minima)
Appears as a 0 or 1 on the relationship line, next to cardinality
Define: Referential Integrity – ANSWER- Requires that ALL foreign key values
must either be fully NULL or match some primary key value
4 Ways Referential Integrity can be violated: – ANSWER- 1. Primary key is
updated<\/p>\n\n\n\n

    \n
  1. Foreign key is updated<\/li>\n\n\n\n
  2. Row containing primary key is DELETED<\/li>\n\n\n\n
  3. Row containing foreign key is INSERTED
    4 Actions to Correct Referential Integrity Violation: – ANSWER- 1. RESTRICT –
    rejects an insert, update, or delete<\/li>\n\n\n\n
  4. SET NULL – sets invalid foreign keys to null<\/li>\n\n\n\n
  5. SET DEFAULT – sets invalid foreign keys to a default primary value<\/li>\n\n\n\n
  6. CASCADE – propagates primary key changes to foreign keys
    What is an important aspect to referential integrity? – ANSWER- reference to data
    in one relation is based on values in another relation
    1 \/ 4
    What is a broad definition of data? – ANSWER- Raw facts captured on printed or
    digital media
    What are data? – ANSWER- Facts that are collected and stored in a database
    system
    What is a determining characteristic of unstructured data? – ANSWER- It does not
    follow a data model
    What is true about flat files? – ANSWER- – They contain no internal hierarchical
    organization
    How were data retrieved before database management systems? – ANSWER\u0002Sequentially from simple files
    What is an attribute or group of attributes that uniquely identify a tuple in a
    relation? – ANSWER- Primary Key
    What is necessary for a primary key in one relation of a database to match with its
    corresponding foreign key in another relation of the same database? – ANSWER\u0002A domain of values
    What uniquely identifies each entity in a collection of entities but is not the
    primary key? – ANSWER- Alternate Key
    What is the term for a set of columns in a table that can uniquely identify any
    record in that table without referring to other data? – ANSWER- Candidate Key
    What happens to the original data in database indexing? – ANSWER- It is copied
    to the index
    Why are indexes created in a physical database design? – ANSWER- To retrieve
    data DIRECTLY using a pointer
    Why is an index created on a database column? – ANSWER- To optimize data
    retrievals
    Define: Functional Dependency – ANSWER- Each value of a column relates to at
    MOST one value of another column
    Dependence of one column on another
    2 \/ 4
    What term is used to describe: a value of one particular attribute associated with a
    specific single value of another attribute? – ANSWER- Functional Dependency
    Rules\/Appearance of First Normal Form – ANSWER- – All non-key columns
    depend on primary key<\/li>\n<\/ol>\n\n\n\n