Tag: databases

Questions Related to databases

  1. to_char

  2. max

  3. cube

  4. rollup


Correct Option: B
Explanation:

To answer this question, the user needs to have knowledge of SQL functions.

A. to_char: This function is used to convert a number or date to a string. It cannot operate on any datatype.

B. max: This function returns the maximum value in a set of values. It can operate on any datatype.

C. cube: This function is used to generate a result set that represents the subtotals and grand totals of the selected columns. It cannot operate on any datatype.

D. rollup: This function is used to generate a result set that represents the subtotals of the selected columns. It cannot operate on any datatype.

Therefore, the correct answer is:

The Answer is: B. max

  1. Primary key access

  2. Full table scan

  3. Access via unique index

  4. Table access by ROWID


Correct Option: D
  1. By value

  2. By reference

  3. By type

  4. none of the above


Correct Option: A
  1. Real abstarct clusters

  2. Real application cursors

  3. Real application clusters

  4. none of the above


Correct Option: C
  1. 10 ^ 6

  2. 10 ^ 9

  3. 10 ^ 12

  4. 10 ^ 15


Correct Option: C
Explanation:

To solve this question, the user needs to know the basic unit of digital storage and its prefixes.

The basic unit of digital storage is a bit, which is represented by either a 0 or a 1. A byte is a group of 8 bits. The prefixes used to represent large amounts of bytes are kilo, mega, giga, and tera.

Now, let's go through each option and explain why it is right or wrong:

A. 10^6: This option is incorrect. One megabyte (MB) is equal to 10^6 bytes. One terabyte (TB) is equal to 10^12 bytes, which is a much larger quantity than 10^6.

B. 10^9: This option is incorrect. One gigabyte (GB) is equal to 10^9 bytes. One terabyte (TB) is equal to 10^12 bytes, which is a much larger quantity than 10^9.

C. 10^12: This option is correct. One terabyte (TB) is equal to 10^12 bytes. This is a very large quantity of data, and is often used to represent the storage capacity of hard drives and other digital storage devices.

D. 10^15: This option is incorrect. One petabyte (PB) is equal to 10^15 bytes. One terabyte (TB) is a much smaller quantity of data than 10^15 bytes.

Therefore, the answer is: C. 10^12