What is a hashing structure? What are the advantage(s) and disadvantage(s) associated with it?
What will be an ideal response?
A hashing structure employs an algorithm that converts the primary key of a record directly into a storage address. Hashing eliminates the need for a separate index. By calculating the address, rather than reading it from an index, records can be retrieved more quickly. The principal advantage of hashing is access speed. The hashing technique has two disadvantages. It does not use storage space efficiently. The storage location chosen for a record is a mathematical function of its primary key value. The algorithm will never select some disk locations because they do not correspond to legitimate key values. Different record keys may generate the same (or similar) residual, which translates to the same address. This is called a collision because two records cannot be stored at the same location.
PTS: 1
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The text contained between title tags is:
a. Not displayed by browsers b. Displayed in the title bar of the browser window c. Not used by search engines d. Never seen by your web page visitor.
Modify the online auction site (Section 26.4) to include a feature that allows users to sell items. Write a document named sell.asp that allows users to auction items. The user enters an item’s information (e.g., price, description, etc.) in a form and submits it. Post the contents to dosell.asp, which inserts the information into the AuctionItems table of the DeitelAuc- tions.mdb database and redirects the user to bookitems.asp. Write dosell.asp. Next, modify the auction site to ensure that users are logged in before allowing them to sell an item. Modify index.asp (Fig. 26.12), login.asp (Fig. 26.21) and checklogin.asp (Fig. 26.22) as follows: If a user is not logged in when the Sell an Item link is clicked, redirect the user to login.asp. Once the user has successfully logged in, redirec
What will be an ideal response?
The ________ changes dynamically when someone enters commands in configuration mode
A) startup-config B) default-config C) running-config D) ram-config
As a general rule,alttext should describe an image without adding additional information, as this text is intended to be able to substitute for the image. _________________________
Answer the following statement true (T) or false (F)