MySQL Basic Data Types and CREATE TABLE ($$$)

You have answered 0 correctly out of 0 attempts.
Read about the numeric data types on page 305 to 307.

Note:
  • The integer types all hold only whole numbers, make sure that you do not choose one that may not hold the future possible range of numbers you will need.
  • Do not use integer types for anything that may have a fractional part.
  • The most common integer type to use is just INT
  • Unless you have a specific reason, you should always use DOUBLE for any number that has a fractional part.
  • For the best compatibility you should leave off the M and D specifiers and just use DOUBLE by it self for all floating point numbers.
  • DOUBLE(10,2) would specify a number up to 10 places and show 2 decimal places. 10 is the display length and 2 is the number of decimals displayed. Neither of these affect the actual precision and storage of the number.
  • DECIMAL is a special type that you can specify the exact display length of up to 64 digits and the number of decimals. This will allow you to store larger precision than even DOUBLE. But it is slower and takes more storage, so only use it for very special circumstances.
Recommend:
  • Only use INT and DOUBLE, without display or decimal specifiers.

Question?

for storing the number of children in a family, which is the best data type?