Give an example of a schedule that would be accepted by a two-phase locking concurrency control but not by a timestamp-ordered concurrency control.
What will be an ideal response?
r1(x) r2(x) w2(y) commit2 w1(x) commit1
This schedule would be accepted by a two-phase locking concurrency control with T2
before T1 in the serial order. However it would not be accepted by a timestamp-ordered
concurrency control because, with such a control, T1 must be before T2 because it
started before T2, and thus T2 should have read the value of x that T1 wrote.
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Variables of the boolean data type are useful for
a. evaluating conditions that are either true or false b. working with small integers c. working with very large integers d. evaluating scientific notation
The color encoding we’re using is RGB. What does this mean, in terms of the amount of memory required to represent color? Is there a limit to the number of colors that we can represent? Are there enough colors representable in RGB?
What will be an ideal response?
Case 5-1Emma is writing a program that will adjust a sound clip's volume.Emma knows that to increase a sound clip's volume, she needs to instruct the program to ____.
A. increase the size of the sample value B. decrease the amplitude C. divide the sound clip's old value by a given factor D. adjust the sound's aspect ratio
When preparing written documents, which of the following is a suggestion that should be kept in mind??
A. ?Keep your writing concise and well-organized. B. ?Use passive voice whenever possible. C. ?Impress your audience with the size of your vocabulary. D. ?Repeat the same word frequently.