Create a new table, field type trade-offs int or smallint

Create a new table, field type select int or smallint?

is the back length as small as possible in the case of enough?
smallint (4) Can you do that?
------Solution--------------------
int 4 bytes
SmallInt 2 bytes
Take up less hard disk space when you are in enough condition

------Solution--------------------
Look at the demand.
Each type has a range, and you need to see if the use will go out of scope to determine.
Int
Integer data from -2^31 "31" (-2,147,483,648) to 2^31-1 (2,147,483,647) (all numbers). The storage size is 4 bytes.

smallint
Integer data from -2^15 (-32,768) to 2^15-1 (32,767). The storage size is 2 bytes.

tinyint
Integer data from 0 to 255. The storage size is 1 bytes.

bigint
Integer data (all numbers) from -2^63 (-9223372036854775808) to 2^63-1 (9223372036854775807). The storage size is 8 bytes.
------Solution--------------------
for ID, unsigned int is sufficient.

