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Tuesday, August 13, 2019

Which of the following backup techniques uses the least amount of space on the backup medium?

Which of the following backup techniques uses the least amount of space on the backup medium?

  • Mirror backup
  • Incremental backup
  • Differential backup
  • Full backup 
 

EXPLANATION

Incremental backup
An incremental backup is one in which successive copies of the data contain only that portion that has changed since the preceding backup copy was made. When a full recovery is needed, the restoration process would need the last full backup plus all the incremental backups until the point of restoration. Incremental backups are often desirable as they reduce storage space usage, and are quicker to perform than differential backups.
A differential backup is a type of data backup that preserves data, saving only the difference in the data since the last full backup. The rationale in this is that, since changes to data are generally few compared to the entire amount of data in the data repository, the amount of time required to complete the backup will be smaller than if a full backup was performed every time that the organization or data owner wishes to back up changes since the last full backup. Another advantage, at least as compared to the incremental backup method of data backup, is that at data restoration time, at most two backup media are ever needed to restore all the data. This simplifies data restores as well as increases the likelihood of shortening data restoration time. 

 

 

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In a database, cardinality refers to:

In a database, cardinality refers to:

  • How many unique values are in a column of a table
  • How many rows a table contains
  • How many columns a table contains
  • Which command gets executed first 
In a database, cardinality refers to:

EXPLANATION


In the context of databases, cardinality refers to the uniqueness of data values contained in a column. High cardinality means that the column contains a large percentage of totally unique values. Low cardinality means that the column contains a lot of “repeats” in its data range.
It is not common, but cardinality also sometimes refers to the relationships between tables. Cardinality between tables can be one-to-one, many-to-one or many-to-many.

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What type of cheese is best

What type of cheese is best

  • Cheddar
  • Swiss
  • Monterrey Jack
  • Gouda 
What type of cheese is best

EXPLANATION


Cheese gives our favorite foods flavor and zest. There’s a reason that the grilled cheese is famous among Americans -- it tastes delicious! But with many delicious foods come a lot of fat and calories.
According to an article in Time Magazine, four out of five experts say that cheese is part of a healthy diet. However, there are certain cheeses that are healthier than others.
Worst: Cheese Products
The FDA has very strict regulations on what is considered a cheese and what is not. According to an article on Eat This, “Anything that’s processed cannot legally be sold as ‘cheese,’ and is marketed instead as a cheese product’—meaning it contains less than 51% cheese.” We know to stay away from processed foods but you may also want to avoid processed cheeses.
Worst: Low-Fat Cheese
Any food that eliminates food, fat, or sugar should be on your radar. These low-fat alternatives can contain harmful ingredients. Not to mention, you miss all of the benefits of full-fat cheese.
Worst: Reduced-Sodium Cheddar
Whenever you see a label that says reduced-fat, reduced-sugar, or reduced anything for that matter, you should find out what they are substituting with. Reduced-sodium foods have the same problem so although low sodium may sound appeal, check your ingredients label before you decide to purchase.
Worst: Sweetened Cream Cheese
Cream cheese may be perfect on a bagel but again, watch out for ingredients. Some cream cheese spreads market that they are healthier, however many of the flavored varieties contain added ingredients such as aspartame, which has been linked to gastrointestinal problems.
Best: Cottage Cheese
Cottage cheese is not only a valuable sources of protein, clocking in at 15 grams per serving, but it is also low in sodium. In a 2014 study, cottage cheese was found to have the lowest sodium measurement among all of the cheeses tested.
Best: Full-fat Cheese
Chuck Benbrook, research professor at Washington State University’s Center for Sustaining Agriculture and Natural Resources, praises organic, full-fat cheese. He conducted a study and found that organic cheese and other dairy products have 62 percent more omega-3 fatty acids than conventional dairy products.
Best: Organic Cheese
Fat is never to blame when it comes to cheese. A recent study in the American Journal of Clinical Nutrition found that people who eat around eight servings of full-fat dairy per day had a 23 percent lower risk of developing type 2 diabetes, compared to people who ate about a serving or less a day. Just be aware of how much a recommended serving size is before you go crazy.
Best: Parmesan Cheese
Parmesan is naturally higher in fat than other cheeses but a little sprinkle goes a long way on a fresh salad or pasta dish. A study published in Flavour found that parmesean cheese is naturally strong in umami, which makes low-fat foods taste better and is known to improve digestion.
Best: Swiss Cheese
Registered dietitian Lindsay Malone told Time that by eating cheese sparingly, you can reap all of the benefits such as calcium, protein. Two slices of Swiss cheese contain 44 percent of your daily calcium intake, and 15 grams of protein.

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Which of these is not a layer in the OSI model?

Which of these is not a layer in the OSI model?

  • Presentation
  • Data Link
  • User
  • Network 
Which of these is not a layer in the OSI model?


EXPLANATION

In OSI Model  User layer is  the 8th layer in the OSI model, but its not offically declared as a one of the layer in OSI model.

 

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Which of the following is NOT commonly abbreviated as MAC?

Which of the following is NOT commonly abbreviated as MAC?

  • Message Authentication Code
  • Managed Architecture Cloud
  • Media Access Control
  • Mandatory Access Control 
Which of the following is NOT commonly abbreviated as MAC?

EXPLANATION

Mandatory access control
In computer security, mandatory access control refers to a type of access control by which the operating system constrains the ability of a subject or initiator to access or generally perform some sort of operation on an object or target.

Message authentication code
In cryptography, a message authentication code, sometimes known as a tag, is a short piece of information used to authenticate a message—in other words, to confirm that the message came from the stated sender and has not been changed.
Media access control
In the IEEE 802 reference model of computer networking, the medium access control or media access control layer is the lower sublayer of the data link layer of the seven-layer OSI model. 

 

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