Author Question: Which type of index is commonly used in data warehousing environments? A) Joint index B) ... (Read 54 times)

tfester

  • Hero Member
  • *****
  • Posts: 534
Which type of index is commonly used in data warehousing environments?
 
  A) Joint index
  B) Bit-mapped index
  C) Secondary index
  D) Tri-dex

Question 2

Discuss when to use the GROUP BY clause.
 
  What will be an ideal response?


cloud

  • Sr. Member
  • ****
  • Posts: 343
Answer to Question 1

B

Answer to Question 2

The GROUP BY clause is useful when you have a set of values for one column (such as a salesperson ID) and you would like to then calculate something like total sales for each salesperson. Rather than having to use the sum function with one salesperson's ID in the WHERE clause (and run multiple queries) you can use the GROUP BY to get the same results in one query.



Related Topics

Need homework help now?

Ask unlimited questions for free

Ask a Question

cloud

  • Sr. Member
  • ****
  • Posts: 343

 

Did you know?

Only 12 hours after an egg cell is fertilized by a sperm cell, the egg cell starts to divide. As it continues to divide, it moves along the fallopian tube toward the uterus at about 1 inch per day.

Did you know?

The effects of organophosphate poisoning are referred to by using the abbreviations “SLUD” or “SLUDGE,” It stands for: salivation, lacrimation, urination, defecation, GI upset, and emesis.

Did you know?

The newest statin drug, rosuvastatin, has been called a superstatin because it appears to reduce LDL cholesterol to a greater degree than the other approved statin drugs.

Did you know?

If you could remove all of your skin, it would weigh up to 5 pounds.

Did you know?

Urine turns bright yellow if larger than normal amounts of certain substances are consumed; one of these substances is asparagus.

For a complete list of videos, visit our video library