A search engine is a web server that responds to client requests to search in its stored indexes and (concurrently) runs several web crawler tasks to build and update the indexes. What are the requirements for synchronization between these concurrent activities?
What will be an ideal response?
The crawler tasks could build partial indexes to new pages incrementally, then merge them with the active
index (including deleting invalid references). This merging operation could be done on an off-line copy.
Finally, the environment for processing client requests is changed to access the new index. The latter might
need some concurrency control, but in principle it is just a change to one reference to the index which should
be atomic.
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Answer the following statements true (T) or false (F)
1. In an entity relationship diagram, rectangles represent entities, and ovals represent relationships. 2. The elements that make up an organizational system are referred to as entities. 3. A crow's foot on each side of a relationship indicates a one-to-one relationship. 4. An associative entity joins two entities. 5. Middle managers make decisions using predetermined rules that have predictable outcomes when implemented correctly.
Data that describes the properties or characteristics of other data is ________
A) metadata B) knowledge C) enhanced data D) information
The ____________________ copies the formatting from one cell or range to another cell or range without duplicating any of the data.
Fill in the blank(s) with the appropriate word(s).
You use Microsoft's free Office Presentation Service to deliver a presentation over the ____________________.
Fill in the blank(s) with the appropriate word(s).