HIM 350 T2 Flashcard
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data dictionary
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contains at least all of the attributes and characteristics for each table in the system; provides description of all tables found within a user/designer created database
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superkey
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any key that uniquely identifies each row
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foreign key
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the primary key of one table that has been placed into another table to create a common attribute
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candidate
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key can be described as a minimal super key, a super key without any unnecessary attributes
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secondary key
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defined as a key that is used strictly for data retrieval purposes
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index
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an orderly arrangement used to logically access rows in a table
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natural join
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links tables by selecting only the rows with common values in their common attributes
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inner join
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only returns matched records from the tables that are being joined
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logical data independence rule
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application programs and ad hoc facilities are logically unaffected when changes are made to the table structures that preserve the original table values (changing order of columns or inserting columns)
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bridge entity
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another name for a composite entity
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date attributes contain calendar dates stored in a special format known as the _________________________
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julian date format
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each table ________ represents an attribute
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column
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synonym
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indicates the use of different names to describe the same attribute
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homonym
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indicates the use of the same attribute name to label different attributes
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________ are important because they are used to ensure that each row in a table is uniquely identifiable
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keys
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referential integrity
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dictates that the foreign key must contain values that match the primary key in the related table, or must contain null
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the customer tables primary key is cus-code. the customer primary key column has no null entries, and all entries are unique. this is an example of ______________________
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entity integrity
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the ________ constraint can be placed on a column to ensure that every row in the table has a value for that column
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not null
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system catalog
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system-created database whose tables store the user/designer created database characteristics and contents
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the _____ relationship is the "relational model ideal" or relational database norm
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1:M
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the _____ relationship should be rare in any relational database design
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1:1
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To be considered minimally relational, the DBMS must support the key relational operators _______, ________, and ________.
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select, project, join
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union compatible
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when two or more tables share the same number of columns and their corresponding columns share the same or compatible domains
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When you define a tables primary key, the DBMS automatically creates an ____________ on the primary key columns you declared
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unique index
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outer joins
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useful when you are trying to determine what values in related tables cause referential integrity problems
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predicate logic
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used extensively in mathematics, provides a framework in which an assertion can be verified as either true or false
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M:N relationships
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can be implemented by creating a new entity in 1:M relationships with the original entities
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PROJECT
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returns only the attributes requested, in the order in which they are requested
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SELECT
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yields values for all rows found in a table that satisfy a given condition
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a primary key is a __________ key chosen to be the primary means by which rows of a table are uniquely identified
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candidate
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a table is also called a ______________ because the relational models creator used the two terms as synonyms
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relation
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unique index
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index in which the index key can have only one pointer value associated with it
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equijoin
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links tables on the basis of an equality condition that compares specified columns of each table
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an index key can have multiple _________
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attributes
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guaranteed access
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rule of relational database that states every value in a table is guaranteed to be accessible through a combination of table name, primary key value, and column name
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If one department chair can chair only one department, and one department can have only one department chair, this shows a _________ relationship
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1:1
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Also used to establish relationships among tables and to ensure the integrity of the data
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keys
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one characteristic of generalization hierarchies is that they are implemented as _______ relationships
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1:1
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cartesian product
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product yields all possible pairs of rows from two tables
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proper _________ design requires carefully defined and controlled data redundancies to function properly
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data warehousing
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proper use of ______ keys is crucial in controlling data redundancy
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foreign
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closure
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use of relational algebra operators on existing relations produces new relations
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system catalog
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detailed system data dictionary that describes all objects within database; table names, creator, creation date, number of columns and rows, data type, etc.
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to avoid nulls, some designers use special codes known as ________ to indicate the absence of some value
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flags
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join
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power behind the relational database allowing the use of independent tables linked by common attributes
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_______ relationships cannot be implemented as such in the relational model
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M:N
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T or F: a data dictionary is sometimes described as "the database designers database" because it records the design decisions about tables and their structures
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true
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T or F: a null is created when you press the enter key or tab key to move to the next entry without making a prior entry of any kind
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true
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T or F: as rare as 1:1 relationships should be, certain conditions absolutely require their use
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true
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T or F: character data can contain any character or symbol intended for mathematical manipulation
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false
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T or F: depending on the sophistication of the application development software, nulls can create problems when functions such as count, average, and sum are used
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true
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T or F: each table in a relational database must have a primary key
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true
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T or F: if the attribute is functionally dependent on a composite key but not on any subset of that key, the attribute is fully functional on the key
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true
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T or F: in a natural join the column on which the join was made occurs twice in the new table
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false
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T or F: only a single attribute, not multiple attributes, can define functional dependence
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false
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T or F: RDBMSs enforce integrity rules automatically
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true
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T or F: relational algebra defines the theoretical way of manipulation table contents using relational operators
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true
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T or F: the difference operator subtracts one table from the other
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true
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T or F: the divide operation uses one single column table as the divisor and one two column table as the dividend
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true
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T or F: the idea of determination is unique to the database environment
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false
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T or F: the 1:M relationship is easily implemented in the relation model by putting the foreign key of the 1 side in the table of the many side as a primary key
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false
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T or F: the order of the rows and columns is important to the DBMS
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false
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T or F: the practical significance of taking the logical view of a database is that it serves as a reminder of the simple file concept of data storage
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true
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T or F: the rows range of permissible values is known as its domain
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false
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T or F: the select operator yields a vertical subset of a table
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false
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T or F: you can think of a table as a persistent representation of a logical relation
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true
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dashed line
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a derived attribute indicated in the chen notation that connects the attribute and an entity
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a relationship is an association between ______
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entities
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composite attribute
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attribute can be further subdivided to yield additional attributes
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simple attribute
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attribute is one that cannot be subdivided
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weak entity
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has a primary key that is partially or totally derived from the parent entity in the relationship
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unary relationship
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exists when an association is maintained within a single entity
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ternary relationship
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exists when three entities are associated
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domain
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set of possible values for a given attribute
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existence dependent
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entity can exist in the database only when it is associated with another related entity occurrence
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complex _______ requirements may dictate data transformations and they may expand the number of entities and attributes within the design
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information
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ideally an entity identifier is composed of _______ attribute
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one
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recursive relationship
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employee within an employee entity has a relationship with itself
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strong entity
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entity can exist apart from all of its related entities and is existence independent
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if tiny college has some departments that are classified as "research only" and do not offer courses, the course entity of the college database would be _______ the department entity
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optional to
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in organizations that generate large number of transactions, ________ are often a top priority in database design
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high processing speeds
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in an ERD cardinality is indicated using _________ notation, where max is the maximum number of associated entities and min represents the minimum number of entities
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(min,max)
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knowing the minimum and maximum number of ______ occurrences is very helpful at the application software level
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entity
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the conceptual model can handle _______ relationships and multivalued attributes
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M:N
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the crows foot symbol with two vertical parallel lines indicates ______ cardinality
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(1,1)
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the decision to store ______ attributes in database tables depends on the processing requirements and the constraints place on a particular application
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derived
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the entity relationship diagram represents the ________ database as viewed by the end user
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conceptual
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the entity relationship model uses the associative entity to represent _____ relationship between two or more entities
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M:N
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the existence of _______ entity indicates that its minimum cardinality is zero
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optional
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first step in building an ERD is
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creating a detailed narrative of the organizations description of operations
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UML notation
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in ERD modeling can be used for both conceptual and implementation modeling
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To simplify the conceptual design, most higher order relationships are decomposed into appropriate equivalent _____ relationships whenever possible
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binary
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when the specific cardinalities are not included on the diagram in crows foot notation, cardinality is implied by the use of ________
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symbols
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when using crows for notation the associative entity is indicated by _________ relationships lines between the parents and associative entity showing a strong relationship
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solid
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cardinality
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expresses the minimum and maximum number of entity occurrences associated with the occurrence of the related entity
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a persons social security number would be an example of a _______ attribute
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single valued
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relationship degree
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indicates the number of entities or participants associated with a relationship
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a relationship ______ is difficult to establish if only one side of the relationship is known
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classification
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a weak entity must be ______ dependent
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existence
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required attribute
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attribute that must have a value
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a ________ attribute need not be physically stored within the database
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derived
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iterative process
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based on repetition of processes and procedures
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a _______ relationship is also known as an identifying relationship
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strong
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failure to understand the distinction between mandatory and optional _______ in relationships might yield designs in which awkward temporary rows must be created just to accommodate the creation of required entities
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participation
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identifying the attributes of entities helps in the better understanding of _______ among entities
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relationships
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in crows foot notation an optional relationship between entities is shown by drawing a _________ on the side of the optional entity
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small circle (O)
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participation is ________ if one entity occurrence does not require a corresponding entity occurrence in a particular relationship
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optional
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the chen notation identifies a weak entity by using a double walled entity _______
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rectangle
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the concept of relationship strength is based on how the _______ of a related entity is defined
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primary key
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when indicating cardinality the first value represents the ______ number of associated entities
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minimum
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_______ are characteristics of entities
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attributes
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________ are underlined in an ER diagram
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identifiers
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documentation
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helps database designers stay on track during the design process and enables them to pick up the design thread when the time comes to modify the design
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T or F: a composite identifier is a primary key composed of more than one attribute
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true
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T or F: a weak entity has a primary key that is partially or totally derived from the parent entity in the relationship
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true
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T or F: a weak relationship exists if the primary key of the related entity contains at least one primary key component of the parent entity
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false
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T or F: an entity in the entity relationship model corresponds to a table in the relational environment
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true
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T or F: composite attributes make it easier to facilitate detailed queries
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false
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T or F: connectivities and cardinalities are established by concise statements known as business rules
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true
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T or F: in a 1:M relationship, to avoid the possibility of referential integrity errors, the data of the "1" side must be loaded first
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true
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T or F: in chen notation there is no way to represent cardinality
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false
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T or F: in implementation terms, an entity is existence dependent if it has a mandatory primary key
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false
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T or F: in chen and crows foot notations an entity is represented with a rectangle containing the entity name
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true
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T or F: in the entity relationship model a table row corresponds to an entity instance
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true
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T or F: in the original chen notation each attribute is represented by an oval with the attribute name connected to an entity rectangle with a line
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true
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T or F: referential integrity and participation are both bidirectional meaning that they must be addressed in both directions along a relationship
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false
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T or F: relationships between entities always operate in one direction
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false
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T or F: software vendors have adopted the chen representation because of its compact representation
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false
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T or F: crow foot notation easily identifies multivalued attributes
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false
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T or F: crows foot notation is less implementation oriented than chen notation
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false
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T or F: ERM is dependent on the database type
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false
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T or F: existence of a mandatory relationship indicates that the minimum cardinality is 0 or 1 for the mandatory entity
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false
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T or F: process of database design is a sequential process
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false
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T or F: to implement a small database a designer must know the "1" and the "M" sides of each relationship and whether the relationships are mandatory or optional
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true
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T or F: unary relationships are common in manufacturing industries
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true
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A relational table must not contain a ___________
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repeating group
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a table is in 4NF if it is in 3NF and ___________
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it has no multivalued dependencies
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anomalies
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what a table yields that displays data redundancies
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1NF
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table that has all key attributes defined, has no repeating groups, and all its attributes are dependent on the primary key
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a table that is in 2NF and contains no transitive dependencies is said to be in ______
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3NF
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4NF
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table where all attributes are dependent on the primary key but are independent of each other and no row contains two or more multivalued facts about an entity
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BCNF
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table where every determinant is a candidate key
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repeating group
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derives its name from the fact that a collection of multiple entries of the same type can exist for any single key attribute occurrence
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partial dependency
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exists when there are functional dependencies such that XY is functionally dependent on WZ, X is functionally dependent on W, and XY is primary key
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transitive dependency
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exists when there are functional dependencies that Y is functionally dependent on X, Z dependent on Y, and X is primary key
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an atomic attribute _______
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can't be further subdivided
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prime attribute
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attribute that is part of a key
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an example of denormalization is using a ________ denormalized table to hold report data
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temporary
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attribute A _______ attribute B if all rows in the table that agree in value for A also agree for B
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determines
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BCNF can be violated only if the table contains more than one ______
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candidate key
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data redundancy produces ____________________
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data integrity problems
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data warehouse routinely uses ______ structures in its complex, multilevel, multi source data environment
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2NF
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partial dependencies
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dependencies based on only a part of a composite primary key
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for most business transactional databases we should normalize relations into _______
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3NF
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from a structural point of view, 2NF is better than ______
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1NF
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from a structural point of view, 3NF is better than _____
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2NF
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from a system functionality point of view, _______ attribute values can be calculated when they are needed to write reports or invoices
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derived
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granularity
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level of detail represented by the values in a tables row
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if a table has multiple candidate keys and one of those candidate keys is a composite key, the table can have _________ based on this composite candidate key even when the primary key chosen is a single attribute
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partial dependencies
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improving _______ leads to more flexible queries
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atomicity
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in a real world environment we must strike a balance between design integrity and ________
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flexibility
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multivalued dependency
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situation where one key determines multiple values of two other attributes and those attributes are independent of each other
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in a ________ diagram the arrows above the attributes indicate all desirable dependencies
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dependency
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normalization works through a series of stages called normal forms. for most purposes in business database design, ______ stages are as high as you need to go in the process
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three
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of the normal forms ______ is mostly of theoretical interest
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DKNF
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some very specialized applications may require normalization beyond the _________
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4NF
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the conflicts between design efficiency, information requirements, and performance are often resolved through ________
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compromises that include denormalization
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the most likely data type for a surrogate key is ______
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numeric
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to generate a surrogate key microsoft access uses an _________ data type
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autonumber
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when a table contains only one candidate key, _______ are considered to be equivalent
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3NF and BCNF
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when designing a database you should _______________
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make sure that entities are in normal form before table structures are created
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______________ databases reflect the ever growing demand for greater scope and depth in the data on which decision support systems increasingly rely
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data warehouse
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a dependency based on only a part of a composite primary key is called a __________
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partial dependency
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entity names
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nouns that are familiar to business, should be short and meaningful, and should document abbreviations, synonyms, and aliases for each entity
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all relational tables satisfy the ________ requirements
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1NF
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an attribute that cannot be further subdivided is said to display ______
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atomicity
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an ERD is created through an ______ process
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iterative
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any attribute that is at least a part of a key is known as a _______
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prime attribute
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any attribute whose value determines other values within a row is known as a _______
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determinant
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because partial dependency can exist only why a tables primary key is composed of several attributes, a table whose ______ key consists of only a single attribute is automatically in 2NF
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primary
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if database tables are treated as though they were files in file system, the _______ never has a chance to demonstrate is superior data handling capabilities
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RDBMS
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in a real world environment, changing granularity requirements might dictate changes in primary key selection, and those changes might ultimately require the use of _______ keys
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surrogate
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in order to meet _______ requirements, you may have to denormalize some portions of a database design
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performance
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in the ______ no row may contain tow or more multivalued facts about an entity
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4NF
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it becomes difficult to create a suitable _______ key when the related table uses a composite primary key
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foreign
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the combination of _____ and ER modeling yields a useful ERD whose entities may now be translated into appropriate table structures
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normalization
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the price paid for increased performance through denormalization is a larger amount of ____
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redundancy
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the problem with transitive dependencies is that they still yield data ________
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anomalies
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the ___________ is central to a discussion of normalization
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concept of keys
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unnormalized tables yield no simple strategies for creating virtual tables known as ______
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views
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when a nonkey attribute is the determinant of a key attribute, the table is in 3NF but not in ______
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BCNF
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when designing a new database structure based on the business requirements of the end users, the database designer will construct a data model using a technique such as _________
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crows foot notation ERDs
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normalization
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process to help reduce the likelihood of data anomalies
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T or F: a dependency of one nonprime attribute on another nonprime attribute is a partial dependency
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false
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T or F: a determinant is any attribute whose value determines other values within a column
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false
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T or F: a good relational DBMS excels at managing denormalized relations
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false
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T or F: a table is in BCNF if every determinant in the table is a foreign key
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false
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T or F: a table is in fourth normal form if it is in third normal form and has no independent multivalued dependencies
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true
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T or F: all relational tables satisfy the 1NF requirements
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true
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T or F: atomic attributes are attributes that can be further subdivided
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false
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T or F: attributes should clearly define participation, connectivity, and document cardinality
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false
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T or F: data redundancy produces data anomalies
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true
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T or F: data stored at their highest level of granularity are said to be atomic data
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false
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T or F: denormalization produces a lower normal form
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true
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T or F: dependencies that are based on only a part of a composite primary key are called transitive dependencies
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false
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T or F: dependency diagrams are very helpful in getting a birds eye view of all the relationships among a tables attributes
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true
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T or F: in order to meet performance requirements, portions of the database design may need to be occasionally denormalized
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true
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T or F: in the context of partial dependencies, data redundancies occur because every row entry requires duplication of data
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true
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T or F: it is possible for a table in 2NF to exhibit transitive dependency where the primary key may rely on one or more nonprime attributes to functionally determine other nonprime attributes
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true
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T or F: normalization is a process that is used for changing attributes to entities
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false
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T or F: normalization is a very important database design ingredient and the highest level is always the most desirable
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false
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T or F: normalization purity is often easy to sustain in the modern database environment
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false
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T or F: normalization represents a micro view of the entities within the ERD
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true
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T or F: normalization works through a series of stages called normal forms
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true
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T or F: relational models view data as part of a table or collection of tables in which all key values must be identified
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true
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T or F: repeating groups must be eliminated by ensuring that each row defines a single entity
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true
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T or F: reporting anomalies in a table can cause a multitude of problems for managers and can be fixed through application programming
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false
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T or F: since partial dependency can exist only if a tables primary key is composed of several attributes, if a table in 1NF has a single attribute primary key, then the table is automatically in 2NF
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true
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T or F: the advantage of higher processing speed must be carefully weighed against the disadvantage of data anomalies
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true
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T or F: combination of normalization and ER modeling yields a useful ERD whose entities can be translated into appropriate relationship structures
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false
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T or F: the objective of normalization is to ensure that each table conforms to the concept of well formed relations
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true
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T or F: unnormalized database tables often lead to various data redundancy disasters in production databases
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true
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a table can be deleted from the database using the ______ command
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drop table
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subquery
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query that is embedded inside another query
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alias
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alternate name given to a column or table in any SQL statement
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according to the rules of precedence, which of the following computations should be completed first? a) performing additions and subtractions b) performing power operations c) performing operations within parentheses
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c) performing operations within parentheses
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all changes in a table structure are made using the ______ command followed by a keyword that produces the specific changes a user wants to make
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alter table
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an example of a command a user would use when making changes to a product table is
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UPDATE PRODUCT SET P_INDATE='18-JAN-2004' WHERE P_CODE='13-Q2/P2'
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in oracle the _______ command is used to change the display for a column for example to place a $ in front of a numeric value
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format
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the query to join the p_descript and p_price fields from the product table and the v_name, v_areacode, v_phone, and v_contact fields from the vendor table where the values of v_code match is
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where product.v_code=vendor. v_code
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the query to join the p_descript and p_price fields from the product table and the v_name, v_areacode, v_phone, and v_contact fields from the vendor table where the values of v_code match and the output is ordered by the price is
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where product.v_code=vendor.v_code; order by product.p_price
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the special operator used to check whether a subquery returns any rows is ________
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exists
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the special operator used to check whether an attribute value is within a range of values is ________
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between
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the special operator used to check whether an attribute value matches a given string pattern is ______
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like
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the SQL aggregate function that gives the number of rows containing non null values for a given column is ________
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count
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the SQL command that allows a user to list the contents of a table is _______
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select
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the SQL command that allows a user to permanently save data changes is _______
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commit
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the SQL data manipulation command HAVING ________
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restricts the selection of grouped rows based on a condition
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the SQL query to output the contents of the employee table sorted by last name, first name, and initial is
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order by emp_lname, emp_fname, emp_initital
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the ________ command is used to restore the database to its previous condition
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rollback
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the _______ command would be used to delete the table row where the p_code is 'BRT-345'
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delete from product where p_code='BRT-345'
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the ______ constraint assigns a value to an attribute when a new row is added to a table
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default
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UPDATE table name ***** [WHERE condition list]; The _______ command replaces the ***** in the syntax of the update command shown above
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SET columnname=expression
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when a user issues the DELETE FROM table name command without specifying a WHERE condition, _______
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all rows will be deleted
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used to select partial table contents
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SELECT ;columns(s); FROMWHERE
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query used to list a unique value for v-code where the list will produce only a list of those values that are different from one another
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SELECT DISTINCT V_CODE FROM PRODUCT
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query used to correct SQL syntax to list the table contents for either v-code=21344 or v_code=24288
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SELECT P_DESCRIPT, P_INDATE, P_PRICE, V_CODE FROM PRODUCT WHERE V_CODE=21344 OR V_CODE=24288
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what query would list all rows in which the inventory stock dates occur on or after January 20, 2016
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WHERE P_INDATE;='20-JAN-2016'
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what query would output the table contents when the value of v-code is equal to 21344
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WHERE V_CODE=21344
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what query would output the table contents when the value of v_code is not equal to 21344
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WHERE V_CODE ;; 21344
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what query would output table contents when the value of the character field p_code is alphabetically less than 1558-QW1
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WHERE P_CODE ;'1558-QW1'
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what query would use the given columns and column aliases from the product table to determine the total value of inventory held on hand
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SELECT P_DESCRIPT, P_QOH, P_PRICE, PQOH*P_PRICE FROM PRODUCT
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a common practice is to create an _______ on any field that is used as a search key in comparison operations in a conditional expression, or when a user wants to list rows in a specific order
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index
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a specialty field in mathematics, known as ______ algebra, is dedicated to the use of logical operators
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boolean
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wildcard character
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symbol that can be used as a general substitute for other characters or commands
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schema
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logical group of database objects such as tables and indexes that are related to each other
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join
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performed when data are retrieved from more than one table at a time
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cascading order sequence
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multilevel ordered sequence that can be created easily by listing several attributes, separated by commas, after the order by clause
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subquery
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also known as a nested query or inner query, is a query that is embedded inside another query
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an alias is especially useful when a table must be joined to itself in an ______ query
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recursive
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DATE() and SYSDATE are special functions that return todays date in MS access and _______ respectively
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oracle
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if a user adds a new column to a table that already has rows, the existing rows will default to a value of ________ for the new column
answer
null
question
in a 1:M relationship a user must always create the table for the ______ side first
answer
1
question
in an INSERT command a user can indicate just the attributes that have required values by listing the _____ inside parentheses after the table name
answer
attribute names
question
in SQL all _________ expressions evaluate to true or false
answer
conditional
question
in SQL environment the word ______ covers both questions and actions
answer
query
question
rows can be grouped into smaller collections quickly and easily using the ______ clause within the select statement
answer
group by
question
basic SQL vocabulary has fewer than _____ words
answer
100
question
SQL data type DATE stores data in the _____ date format
answer
julian
question
the ______ clause of the GROUP BY statement operates very much like the WHERE clause in SELECT statement
answer
having
question
the _____ command, coupled with appropriate search conditions, is an incredibly powerful tool that enables a user to transform data into information
answer
select
question
the ____ condition is generally composed of an equality comparison between the foreign key and primary key of related tables
answer
join
question
the _______ specification is used to avoid having duplicated values in a column
answer
UNIQUE
question
to delte an index, one must use the ______ command
answer
DROP INDEX
question
to make SQL code more _____, most SQL programmers use one line per column definition
answer
readable
question
US state abbreviations are always two characters, so _______ (2) is a logical choice for the data type representing a state column
answer
CHAR
question
with the exception of the database ________ process, most RDBMS vendors use SQL that deviates little from the ANSI standard SQL
answer
creation
question
______ words are words used by SQL to perform specific functions
answer
reserved
question
________ is the process the DBMS uses to verify that only registered users access the database
answer
authentication
question
T or F: a database language enables the user to perform complex queries designed to transform the raw data into useful information
answer
true
question
T or F: all SQL commands must be issued on a single line
answer
false
question
T or F: although SQL commands can be grouped together on a single line, complex command sequences are best shown on separate lines with space between the SQL command and the components
answer
true
question
T or F: an alias cannot be used when a table is required to be joined to itself in a recursive query
answer
false
question
T or F: ansi-standard SQL allows the use of special operators in conjunction with the where clause
answer
true
question
T or F: any changes made to the contents of a table are not physically saved on disk until you use the save command
answer
false
question
T or F: data type selection is usually dictated by the nature of the data and by the intended use
answer
true
question
T or F: date procedures are often more software specific than other SQL procedures
answer
true
question
T or F: entity integrity is enforced is enforced automatically when the primary key is specified in the create table command sequence
answer
true
question
T or F: if you have not yet used the commit command to store the changes permanently in the database, you can restore the database to its previous condition with the rollback command
answer
true
question
T or F: mathematical operators cannot be used to place restrictions on character based attributes
answer
false
question
T or F: most SQL implementations yield case insensitive searches
answer
false
question
T or F: only numeric data types can be added and subtracted in SQL
answer
false
question
T or F: oracle users can use the access QBE query generator
answer
false
question
T or F: some RDBMSs such as microsoft access automatically make the necessary conversations to eliminate case sensitivity
answer
true
question
T or F: SQL allows the use of logical restrictions on its inquiries such as or, and , and not
answer
true
question
T or F: SQL is considered difficult to learn; its command set has a vocabulary of more than 300 words
answer
false
question
T or F: SQL requires the use of the ADD command to enter data into a table
answer
false
question
T or F: string comparisons are made from left to right
answer
true
question
T or F: the ansi prescribes a standard SQL-the current fully approved version is known as SQL-07
answer
false
question
T or F: ansi SQL standards are also accepted by the ISO
answer
true
question
T or F: the check constraint used to define a condition for the values that the attribute domain cannot have
answer
false
question
T or F: the commit command does not permanently save all changes; in order to do that you must use save
answer
false
question
T or F: the conditional LIKE must be used in conjunction with wildcard characters
answer
true
question
T or F: the COUNT function is designed to tally the number of non-null values of an attribute and is often in conjunction with the distinct clause
answer
true
question
T or F: to list the contents of a table you must use display command
answer
false
question
T or F: when joining three or more tables, you need to specify a join condition for one pair of tables
answer
false
question
T or F: you can select partial table contents by naming the desired fields and by placing restrictions on the rows to be included in the output
answer
true
question
T or F: you cannot insert a row containing a null attribute value using SQL
answer
false
question
T or F: it is possible for a table in 2NF to exhibit transitive dependency where the primary key may rely on one or more nonprime attributes to functionally determine other nonprime attributes
answer
ture
question
T or F: dependencies that are based on only a part of a composite primary key are called transitive dependencies
answer
false