Name three record-based data models. Discuss the main differences between these data models.
What will be an ideal response?
? relational data model - data and relationships are represented as tables, each of which
has a number of columns with a unique name
? network data model - data is represented as collections of records, and relationships are
represented by sets. Compared with the relational model, relationships are explicitly
modeled by the sets, which become pointers in the implementation. The records are
organized as generalized graph structures with records appearing as nodes (also called
segments) and sets as edges in the graph
? hierarchical data model - restricted type of network model. Again, data is represented as
collections of records and relationships are represented by sets. However, the hierarchical
model allows a node to have only one parent. A hierarchical model can be represented as
a tree graph, with records appearing as nodes (also called segments) and sets as edges.
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Which of the following statements is false?
a. Interface IntPredicate’s default method and performs a logical AND operation with short- circuit evaluation between the IntPredicate on which it’s called and its IntPredicate argument. b. Interface IntPredicate’s default method invert reverses the boolean value of the IntPredicate on which it’s called. c. Interface IntPredicate default method or performs a logical OR operation with short-circuit evaluation between the IntPredicate on which it’s called and its IntPredicate argument. d. You can use the interface IntPredicate default methods to compose more complex conditions.
When in Slide Sorter view, how would you know that hidden slides are included?
What will be an ideal response?
If you attempt to delete a file or folder that does not exist, or if you try to delete a folder that is not empty, Ruby will ignore the error and substitute an empty file.
Answer the following statement true (T) or false (F)
On the Ribbon, you can click the Design tab to view themes. You can then click the More button in the Themes group to open a ____ of themes and see all the thumbnails.
A. gallery B. library C. toolbar D. palette