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Database Processing, 13e (Kroenke/Auer) Chapter 6: Transforming Data Models into Database Designs 1) The first step in the database design process is to create tables and columns from entities and attributes. Answer: TRUE Diff: 2 Page Ref: 231 Fig 6-1 2) When creating a relational database design from E-R diagrams, first create a relation for each relationship. Answer: FALSE Diff: 3 Page Ref: 231 Fig 6-1 3) Each entity in the extended E-R model is represented as a table in the relational database design. Answer: TRUE Diff: 1 Page Ref: 231 Fig 6-1 4) An entity needs to be examined according to normalization criteria before creating a table from it in the relational database design. Answer: FALSE Diff: 2 Page Ref: 231-236 Fig 6-1 5) When creating a table in the relational database design from an entity in the extended E-R model, the attributes of the entity become the rows of the table. Answer: FALSE Diff: 1 Page Ref: 204 Fig 6-1 6) By default, the identifier of the entity becomes the foreign key of the corresponding table. Answer: FALSE Diff: 1 Page Ref: 232-233 7) The ideal primary key is short, numeric, and fixed. Answer: TRUE Diff: 2 Page Ref: 232-233 8) A surrogate key is appropriate when the primary key of a table contains a lengthy text field. Answer: TRUE Diff: 1 Page Ref: 232-233 9) One of the important properties of an attribute is whether or not it is required. Answer: TRUE Diff: 2 Page Ref: 234 10) A surrogate key is a unique, system-supplied identifier used as the primary key of a table. Answer: TRUE Diff: 1 Page Ref: 232-233 1 ScholarStock

11) The values of a surrogate key have no meaning to the users. Answer: TRUE Diff: 2 Page Ref: 232-233 12) A surrogate key should be considered when the key contains a lengthy text field. Answer: TRUE Diff: 3 Page Ref: 232-233 13) Whether or not an attribute is required is determined during the database modeling phase. Answer: FALSE Diff: 3 Page Ref: 234 14) A null value is an attribute value that has been set to zero. Answer: FALSE Diff: 3 Page Ref: 234 15) Data types are consistent across all DBMS products. Answer: FALSE Diff: 1 Page Ref: 234 16) A default value is the value the user enters into the row the first time the user enters data. Answer: FALSE Diff: 1 Page Ref: 235 17) A data constraint is a limitation on data values. Answer: TRUE Diff: 1 Page Ref: 236 18) The last step in creating a table is to verify table normalization. Answer: TRUE Diff: 1 Page Ref: 236 Fig 6-1 19) One of the important properties of a column is whether or not it can have a NULL value. Answer: TRUE Diff: 2 Page Ref: 234 20) A foreign key is a key that does not belong in any table. Answer: FALSE Diff: 2 Page Ref: 236 21) In a relational database design, all relationships are expressed by creating a foreign key. Answer: TRUE Diff: 1 Page Ref: 236

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22) When the key of one table is placed into a second table to represent a relationship, the key is called a "relational key" in the second table. Answer: FALSE Diff: 2 Page Ref: 236 23) To represent a 1:1 binary relationship in a relational database design, the key of one table is placed into the second table. Answer: TRUE Diff: 2 Page Ref: 237 24) When placing a foreign key for a 1:1 relationship, the key of either table can be used as the foreign key in the other table. Answer: TRUE Diff: 1 Page Ref: 237 25) In a 1:1 relationship, the foreign key is defined as an alternate key to make the DBMS enforce uniqueness. Answer: TRUE Diff: 2 Page Ref: 237 26) In a 1:N relationship, the term "parent" refers to the table on the "many" side of the relationship. Answer: FALSE Diff: 1 Page Ref: 238 27) In 1:N relationships, the table on the "one" side is called the parent. Answer: TRUE Diff: 1 Page Ref: 238 28) In representing a 1:N relationship in a relational database design, the key of the table representing the parent entity is placed as a foreign key in the table representing the child entity. Answer: TRUE Diff: 2 Page Ref: 238 29) In representing a 1:N relationship in a relational database design, the key of the table representing the entity on the "many" side is placed as a foreign key in the table representing the entity on the "one" side of the relationship. Answer: FALSE Diff: 3 Page Ref: 238 30) To represent a 1:N relationship in a relational database design, an intersection table is created. Answer: FALSE Diff: 2 Page Ref: 238-240

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31) In 1:N relationships, the table on the "many" side is called the child. Answer: TRUE Diff: 2 Page Ref: 238 32) To represent a one-to-many relationship in a relational database design, the key of the child table is placed as a foreign key into the other table. Answer: FALSE Diff: 2 Page Ref: 238 33) To represent an M:N relationship in a relational database design, a table is created to represent the relationship itself. Answer: TRUE Diff: 2 Page Ref: 238-240 34) To represent an M:N relationship in a relational database design, an intersection table is created. Answer: TRUE Diff: 1 Page Ref: 238-240 35) To represent an M:N relationship in a relational database design, in essence it is reduced to two 1:N relationships. Answer: TRUE Diff: 3 Page Ref: 238-240 36) The key of an intersection table is always the combination of the keys of both parents. Answer: TRUE Diff: 2 Page Ref: 239-240 37) In many-to-many relationships in a relational database design, the primary keys of both tables are joined into a composite primary key in the intersection table. Answer: TRUE Diff: 2 Page Ref: 239-240 38) An intersection table is always ID-dependent on both of its parent tables. Answer: TRUE Diff: 2 Page Ref: 239-240 39) An intersection table can have additional attributes besides the keys of its parent tables. Answer: FALSE Diff: 2 Page Ref: 239-240 40) Like all ID-dependent relationships, the parents of an association table are required. Answer: TRUE Diff: 2 Page Ref: 240-242

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41) Association tables sometimes connect more than two entities. Answer: TRUE Diff: 2 Page Ref: 240-242 42) An ID-dependent table can be used to represent multivalued attributes. Answer: TRUE Diff: 1 Page Ref: 243 43) All identifying relationships are 1:N. Answer: TRUE Diff: 3 Page Ref: 243 44) When creating a table for an ID-dependent entity, both the key of the parent and the key of the entity itself must appear in the table. Answer: TRUE Diff: 3 Page Ref: 243 45) The design transformation for all IS-A relationships can be summarized by the phrase "place the key of the parent table in the child table." Answer: FALSE Diff: 3 Page Ref: 247 46) When transforming an ID-dependent E-R data model relationship into a relational database design where the child entity is designed to use a surrogate key, the relationship changes to a weak but not ID-dependent relationship. Answer: TRUE Diff: 2 Page Ref: 247 47) When transforming supertype/subtype entities into a relational database design, an entity is created for the supertype only. Answer: FALSE Diff: 1 Page Ref: 247 48) When transforming supertype/subtype entities into a relational database design, the key of the supertype table is placed into the subtype table typically as the key. Answer: TRUE Diff: 2 Page Ref: 247 49) To represent an IS-A relationship in a relational database design, the IS-A relationship must be converted into a HAS-A relationship. Answer: FALSE Diff: 3 Page Ref: 247 50) Discriminator attributes can be represented in relational designs. Answer: FALSE Diff: 2 Page Ref: 247 5 ScholarStock

51) When transforming supertype/subtype entities into a relational database design, all of the attributes for the supertype table are placed into the subtype relations. Answer: FALSE Diff: 3 Page Ref: 247 52) When transforming an extended E-R model into a relational database design, recursive relationships are treated fundamentally the same as other HAS-A relationships. Answer: TRUE Diff: 3 Page Ref: 247 53) Recursive M:N relationships are represented with an intersection table that shows pairs of related rows from a single table. Answer: TRUE Diff: 3 Page Ref: 246 54) Referential integrity constraints should disallow adding a new row to a child table when the foreign key does not match a primary key value in the parent table. Answer: TRUE Diff: 2 Page Ref: 253 Fig 6-28(a) 55) A referential integrity constraint policy that insures that foreign key values in a table are correctly maintained when there is a change to the primary key value in the parent table is called cascading changes. Answer: FALSE Diff: 1 Page Ref: 255 56) A referential integrity constraint policy that insures that all rows containing a particular foreign key value in a table are eliminated from the table when the row containing the corresponding primary key value in a parent table is eliminated from the database is called cascading deletes. Answer: TRUE Diff: 1 Page Ref: 255 57) When the parent entity is required (M) in a relationship, every row of the child table must have a valid, non-null value of the foreign key. Answer: TRUE Diff: 2 Page Ref: 255 58) Cascading deletions are generally not used with relationships between strong entities. Answer: TRUE Diff: 2 Page Ref: 255 59) Cascading deletions are generally not used with relationships for weak child entities. Answer: FALSE Diff: 2 Page Ref: 255

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60) If the parent is required, then a new child row must be created with a valid foreign key value. Answer: TRUE Diff: 2 Page Ref: 255 61) When the parent entity has a surrogate key, the enforcement actions are the same for both parent and child. Answer: FALSE Diff: 3 Page Ref: 256 62) When the child entity is required (M) in a relationship, there needs to be at least one child row for each parent row at all times. Answer: TRUE Diff: 2 Page Ref: 256 63) It is easy to enforce the referential integrity actions for M-M relationships. Answer: FALSE Diff: 1 Page Ref: 258 64) Which of the following is not a step in the database design process? A) Create tables and columns from entities and attributes B) Select primary keys C) Represent relationships D) Create constraints and triggers E) All of the above are steps in the database design process. Answer: D Diff: 2 Page Ref: 231 Fig 6-1 65) The first step in transforming an extended E-R model into a relational database design is to ________. A) create a table for each relationship B) evaluate the entities against the normalization criteria C) create a table for each entity D) remove any recursive relationships E) document referential integrity constraints Answer: C Diff: 1 Page Ref: 231 Fig 6-1 66) Each attribute of an entity becomes a(n) ________ of a table. A) column B) primary key C) foreign key D) alternate key E) B or D Answer: A Diff: 1 Page Ref: 231 Fig 6-1

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67) The identifier of the entity becomes the ________ of the corresponding table. A) primary key B) foreign key C) supertype D) subtype E) either A or B Answer: A Diff: 1 Page Ref: 231 68) The ideal primary key is ________. A) short B) numeric C) fixed D) A and B E) A, B, and C Answer: E Diff: 2 Page Ref: 232 69) A surrogate key should be considered when ________. A) a relationship is M:N B) a composite key is required C) the key contains a lengthy text field D) the key contains a number E) an index needs to be created Answer: C Diff: 3 Page Ref: 232 70) Which of the following is not true about surrogate keys? A) They are identifiers that are supplied by the system, not the users. B) They have no meaning to the users. C) They are nonunique within a table. D) They can be problematic when combining databases. E) The DBMS will not allow their values to be changed. Answer: C Diff: 2 Page Ref: 232 71) One of the important properties of a column is whether or not it is ________. A) found in more than one entity B) required C) character or numeric D) subject to normalization E) subject to denormalization Answer: B Diff: 2 Page Ref: 234-236

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72) In a relational database design, all relationships are expressed by ________. A) creating a primary key B) creating a foreign key C) creating a supertype D) creating a subtype E) creating a line between entities Answer: B Diff: 1 Page Ref: 236 73) When representing a 1:1 relationship in a relational database design, ________. A) the key of each table must be placed as foreign keys into the other B) the key of either table may be placed as a foreign key into the other C) the key of both tables must be the same D) the intersection table gets the key from both relations E) B and C Answer: B Diff: 1 Page Ref: 237 74) To represent a one-to-many relationship in a relational database design, ________. A) the key of the child is placed as a foreign key into the parent B) the key of the parent is placed as a foreign key into the child C) an intersection table must be created D) the key of the table on the "many" side is placed in the table on the "one" side E) the keys of both tables are joined into a composite key Answer: B Diff: 2 Page Ref: 238 75) When representing a one-to-many relationship in a relational database design, ________. A) the parent is always on the one side of the "one-to-many" relationship B) the child is always on the one side of the "one-to-many" relationship C) either parent or child can be on the one side of the "one-to-many" relationship, and the choice is arbitrary D) either parent or child can be on the one side of the "one-to-many" relationship, and special criteria indicate which table should be on the one side E) None of the above is correct. Answer: A Diff: 2 Page Ref: 238 76) Many-to-many relationships are represented by ________. A) two tables with an M:N relationship B) two tables with a 1:N relationship C) an intersection table which has M:N relationships with the two tables D) an intersection table which has 1:N relationships with the two tables E) two intersection tables which each have 1:N relationships with the two tables Answer: D Diff: 2 Page Ref: 238-240 9 ScholarStock

77) In many-to-many relationships in a relational database design, ________. A) the key of the child is placed as a foreign key into the parent B) the key of the parent is placed as a foreign key into the child C) the keys of both tables are placed in a third table D) the keys of both tables are joined into a composite key E) C and D Answer: E Diff: 2 Page Ref: 238-240 78) In many-to-many relationships in a relational database design, ________. A) the intersection table is ID-dependent on one of the parents B) the intersection table is ID-dependent on both of the parents C) the minimum cardinality from the intersection table to the parents is always M D) A and B E) B and C Answer: E Diff: 3 Page Ref: 238-240 79) In relational database design, ID-dependent entities are used to ________. A) represent N:M relationships B) handle associative relationships C) handle multivalued attributes D) handle archetype/instance relationships E) All of the above. Answer: E Diff: 2 Page Ref: 240 Fig 6-11 80) When transforming an E-R data model into a relational database design, the key of the parent entity should be placed as part of the primary key into the child entity ________. A) when the child entity is ID-dependent B) when the child entity is non-ID-dependent C) when the child entity has a 1:1 relationship with the parent entity D) when the child entity has a 1:N relationship with the parent entity E) when the child entity has a recursive relationship with the parent entity Answer: A Diff: 2 Page Ref: 240-247 81) When transforming an ID-dependent E-R data model relationship into a relational database design and the parent entity has a surrogate primary key and the child entity has a data identifier, then the primary key of the child table should be ________. A) the parent's surrogate key + the child's data key B) the parent's surrogate key + a surrogate key in the child C) either A or B will work, and neither way is preferable D) either A or B will work, but method A is preferable E) either A or B will work, but method B is preferable Answer: E Diff: 3 Page Ref: 240-247 10 ScholarStock

82) When transforming an ID-dependent E-R data model relationship into a relational database design and the child entity is designed to use a surrogate key, then ________. A) the parent entity must also use a surrogate key B) the relationship remains an ID-dependent relationship C) the relationship changes to a non-ID-dependent relationship D) A and B E) A and C Answer: C Diff: 2 Page Ref: 245 83) Which of the following is not true about representing subtypes in a relational database design? A) One table is created for the supertype and one for each subtype. B) All of the attributes of the supertype are added to the subtype relations. C) The key of the supertype is made the key of the subtypes. D) A subtype and its supertype are representations of the same underlying table. E) An instance of the supertype may be related to one instance each of several subtypes. Answer: B Diff: 2 Page Ref: 247 84) In a supertype-subtype structure, discriminator attributes ________. A) are easily represented in a relational design B) cannot be represented in a relational design C) require application logic to determine which subtypes correspond to a specific supertype instance D) A and C E) B and C Answer: E Diff: 3 Page Ref: 247 85) Which of the following is not true of recursive relationships? A) When the recursive relationship is M:N, an intersection table is created. B) The rows of a single table can play two different roles. C) The techniques for representing the tables are the same as for non-recursive relationships except the rows are in the same table. D) Recursive relationships can be 1:1, 1:N, or M:N relationships. E) Even when the relationship is 1:N, a new table must be defined to represent the relationship. Answer: E Diff: 2 Page Ref: 247-249

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86) Which of the following is not true of ternary relationships? A) Can be treated as a collection of binary relationships B) Are represented in the same way as binary relationships C) Must involve at least one M:N relationship D) Involve three entities of different logical types E) Often require documentation of special considerations as business rules Answer: C Diff: 3 Page Ref: 249-251 87) The binary constraint MUST NOT indicates that ________. A) a specific binary relationship must not be included in a ternary relationship B) a table includes values that must not occur in a binary relationship C) a table includes values that must not occur in a ternary relationship D) a binary relationship includes value combinations that must not occur in a binary relationship E) a binary relationship includes value combinations that must not occur in a ternary relationship Answer: E Diff: 2 Page Ref: 249-251 88) The binary constraint MUST COVER indicates that ________. A) a specific binary relationship must be included in a ternary relationship B) a table includes values that must occur in a binary relationship C) a table includes values that must occur in a ternary relationship D) a binary relationship includes value combinations that must occur in a binary relationship E) a binary relationship includes a set of value combinations that must all occur in a ternary relationship Answer: E Diff: 2 Page Ref: 249-251 89) To which of the following actions are referential integrity constraints not applied? A) create B) insert C) modify D) delete E) Referential integrity constraints are applied to all of the listed actions. Answer: A Diff: 2 Page Ref: 253-255 Fig 6-28 90) A referential integrity constraint policy that insures that foreign key values in a table are correctly maintained when there is a change to the primary key value in the parent table is called ________. A) incremental updates B) incremental deletes C) controlled key adjustments D) cascading updates E) cascading deletes Answer: D Diff: 1 Page Ref: 255 12 ScholarStock

91) A referential integrity constraint policy that insures that all rows containing a particular foreign key value in a table are eliminated from the table when the row containing the corresponding primary key value in a parent table is eliminated from the database is called ________. A) incremental updates B) incr...