WGU C170 DATA MANAGEMENT
APPLICATIONS GSA1 FINAL TEST QUESTIONS
◍ composite entity.
Answer: An entity designed to transform an M:N relationship into two 1:M
relationships. The composite entity's primary key comprises at least the
primary keys of the entities that it connects. Also known as a bridge entity
or associative entity. See also linking table.
◍ AREA.
Answer: In DB2, a named section of permanent storage space that is
reserved to store the database.
◍ IS NULL.
Answer: In SQL, a comparison operator used to check whether an attribute
has a value.
◍ outer join.
Answer: A join operation that produces a table in which all unmatched pairs
are retained; unmatched values in the related table are left null
◍ multivalued attributes.
Answer: An attribute that can have many values for a single entity
occurrence. For example, an EMP_DEGREE attribute might store the string
"BBA, MBA, PHD" to indicate three different degrees held.
◍ SUBSTRING.
Answer: This string operator returns a part of a given string parameter.
◍ bridge entity.
, Answer: See composite entity.
◍ CREATE INDEX.
Answer: A SQL command that creates indexes on the basis of a selected
attribute or attributes.
◍ cardinality.
Answer: A property that assigns a specific value to connectivity and
expresses the range of allowed entity occurrences associated with a single
occurrence of the related entity.
◍ Base table.
Answer: The table on which a view is based.
◍ primary key (PK).
Answer: In the relational model, an identifier composed of one or more
attributes that uniquely identifies a row. Also, a candidate key selected as a
unique entity identifier. See also key.
◍ UNION.
Answer: In relational algebra, an operator used to merge (append) two tables
into a new table, dropping the duplicate rows. The tables must be
union-compatible.
◍ Table space.
Answer: In a DBMS, logical storage space used to group related data. Also
known as a file group.
◍ Database performance tuning.
Answer: A set of activities and procedures designed to reduce the response
time of a database system—that is, to ensure that an end-user query is
processed by the DBMS in the minimum amount of time.
◍ Create a table with constraint functions.
Answer: CREATE TABLE TableName (ColumnName1 DataType
Constraint1 Constraint2,ColumnName2 DataType Constraint1);
◍ B-tree index.
, Answer: An ordered data structure organized as an upside-down tree.
◍ Set a foreign key on an existing table.
Answer: ALTER TABLE TableNameADD FORIEGN KEY (Column)
REFERENCE Table (Column);
◍ Adding start and end foreign keys to the fact table for slowly-changing
dimensions..
Answer: Type 2 Design
◍ 37. Which data type can be designated to allow for storage of datesa.
VARCHARb. INTEGERc. DECIMALd. TIMESTAMP/DATE.
Answer: TIMESTAMP/DATE
◍ Association Rules.
Answer: Association rules specify a relation between attributes that appears
more frequently than expected if the attributes were independent.
◍ States that every value of a foreign key must match a value of an existing
primary key or be fully NULL..
Answer: Referential Integrity
◍ Ternary Relationship.
Answer: Involves three different entity types.
◍ 48. Write a query to list customers from Chicago or Seattle..
Answer: SELECT *FROM CustomerWHERE City = 'Chicago' OR City =
'Seattle';
◍ RESTRICT.
Answer: See SELECT.
◍ hash index.
Answer: An index based on an ordered list of hash values.
◍ Cross join.
Answer: A join that performs a relational product (or Cartesian product) of
two tables e.g. (table A \* table B)SELECT \* FROM T1, T2
, ◍ % of table rows selected by a query.
Answer: Hit Ration
◍ Static query optimization.
Answer: A query optimization mode in which the access path to a database
is predetermined at compilation time.
◍ regular entity.
Answer: See strong entity.
◍ Index scan (range).
Answer: Reads the index first to obtain the row IDs and then accesses the
table rows directly (faster than a full table scan)
◍ query processing bottleneck.
Answer: In query optimization, a delay introduced in the processing of an
I/O operation that causes the overall system to slow down.
◍ MAX.
Answer: A SQL aggregate function that yields the maximum attribute value
in a given column.
◍ 1NF.
Answer: Normal form: No repeating groups, PK identified, all values
depend on PK
◍ Third Normal Form.
Answer: Non-key attributes are not allowed to define other non-key
attributes.
◍ correlated subquery.
Answer: A subquery that executes once for each row in the outer query.
◍ ternary relationship.
Answer: An ER term used to describe an association (relationship) between
three entities. For example, a DOCTOR prescribes a DRUG for a
PATIENT.
◍ existence-dependent.
APPLICATIONS GSA1 FINAL TEST QUESTIONS
◍ composite entity.
Answer: An entity designed to transform an M:N relationship into two 1:M
relationships. The composite entity's primary key comprises at least the
primary keys of the entities that it connects. Also known as a bridge entity
or associative entity. See also linking table.
◍ AREA.
Answer: In DB2, a named section of permanent storage space that is
reserved to store the database.
◍ IS NULL.
Answer: In SQL, a comparison operator used to check whether an attribute
has a value.
◍ outer join.
Answer: A join operation that produces a table in which all unmatched pairs
are retained; unmatched values in the related table are left null
◍ multivalued attributes.
Answer: An attribute that can have many values for a single entity
occurrence. For example, an EMP_DEGREE attribute might store the string
"BBA, MBA, PHD" to indicate three different degrees held.
◍ SUBSTRING.
Answer: This string operator returns a part of a given string parameter.
◍ bridge entity.
, Answer: See composite entity.
◍ CREATE INDEX.
Answer: A SQL command that creates indexes on the basis of a selected
attribute or attributes.
◍ cardinality.
Answer: A property that assigns a specific value to connectivity and
expresses the range of allowed entity occurrences associated with a single
occurrence of the related entity.
◍ Base table.
Answer: The table on which a view is based.
◍ primary key (PK).
Answer: In the relational model, an identifier composed of one or more
attributes that uniquely identifies a row. Also, a candidate key selected as a
unique entity identifier. See also key.
◍ UNION.
Answer: In relational algebra, an operator used to merge (append) two tables
into a new table, dropping the duplicate rows. The tables must be
union-compatible.
◍ Table space.
Answer: In a DBMS, logical storage space used to group related data. Also
known as a file group.
◍ Database performance tuning.
Answer: A set of activities and procedures designed to reduce the response
time of a database system—that is, to ensure that an end-user query is
processed by the DBMS in the minimum amount of time.
◍ Create a table with constraint functions.
Answer: CREATE TABLE TableName (ColumnName1 DataType
Constraint1 Constraint2,ColumnName2 DataType Constraint1);
◍ B-tree index.
, Answer: An ordered data structure organized as an upside-down tree.
◍ Set a foreign key on an existing table.
Answer: ALTER TABLE TableNameADD FORIEGN KEY (Column)
REFERENCE Table (Column);
◍ Adding start and end foreign keys to the fact table for slowly-changing
dimensions..
Answer: Type 2 Design
◍ 37. Which data type can be designated to allow for storage of datesa.
VARCHARb. INTEGERc. DECIMALd. TIMESTAMP/DATE.
Answer: TIMESTAMP/DATE
◍ Association Rules.
Answer: Association rules specify a relation between attributes that appears
more frequently than expected if the attributes were independent.
◍ States that every value of a foreign key must match a value of an existing
primary key or be fully NULL..
Answer: Referential Integrity
◍ Ternary Relationship.
Answer: Involves three different entity types.
◍ 48. Write a query to list customers from Chicago or Seattle..
Answer: SELECT *FROM CustomerWHERE City = 'Chicago' OR City =
'Seattle';
◍ RESTRICT.
Answer: See SELECT.
◍ hash index.
Answer: An index based on an ordered list of hash values.
◍ Cross join.
Answer: A join that performs a relational product (or Cartesian product) of
two tables e.g. (table A \* table B)SELECT \* FROM T1, T2
, ◍ % of table rows selected by a query.
Answer: Hit Ration
◍ Static query optimization.
Answer: A query optimization mode in which the access path to a database
is predetermined at compilation time.
◍ regular entity.
Answer: See strong entity.
◍ Index scan (range).
Answer: Reads the index first to obtain the row IDs and then accesses the
table rows directly (faster than a full table scan)
◍ query processing bottleneck.
Answer: In query optimization, a delay introduced in the processing of an
I/O operation that causes the overall system to slow down.
◍ MAX.
Answer: A SQL aggregate function that yields the maximum attribute value
in a given column.
◍ 1NF.
Answer: Normal form: No repeating groups, PK identified, all values
depend on PK
◍ Third Normal Form.
Answer: Non-key attributes are not allowed to define other non-key
attributes.
◍ correlated subquery.
Answer: A subquery that executes once for each row in the outer query.
◍ ternary relationship.
Answer: An ER term used to describe an association (relationship) between
three entities. For example, a DOCTOR prescribes a DRUG for a
PATIENT.
◍ existence-dependent.
