What is the difference between tinyint, mediumint, bingint and int in sql?

Question

What is the difference between tinyint, mediumint, bingint and int in sql?

In which case are used?

Answer 1

The difference is the amount of memory allocated to each integer, and how large a number they each can store.

Answer 2

They take up different amounts of space and they have different ranges of acceptable values.

Here are the sizes and ranges of values for SQL Server, other RDBMSes have similar documentation:

• MySQL
• Postgres
• Oracle (they just have a NUMBER datatype really)
• DB2

Turns out they all use the same specification (with a few minor exceptions noted below) but support various combinations of those types (Oracle not included because it has just a NUMBER datatype, see the above link):

              SQL Server    MySQL   Postgres    DB2
tinyint           X           X                 
smallint          X           X         X        X
mediumint                     X
int / integer     X           X         X        X  
bigint            X           X         X        X

And they support the same value ranges (with one exception below) and all have the same storage requirements:

• tinyint: 1 byte, -128 to +127 / 0 to 255 (unsigned)
• smallint: 2 bytes, -32,768 to +32,767 / 0 to 65,535 (unsigned)
• mediumint: 3 bytes, -8,388,608 to 8,388,607 / 0 to 16,777,215 (unsigned)
• int/integer: 4 bytes, -2,147,483,648 to +2,147,483,647 / 0 to 4,294,967,295 (unsigned)
• bigint: 8 bytes, -9,223,372,036,854,775,808 to 9,223,372,036,854,775,807 / 0 to 18,446,744,073,709,551,615 (unsigned)

The "unsigned" types are only available in MySQL, and the rest just use the signed ranges, with one notable exception: tinyint in SQL Server is unsigned and has a value range of 0 to 255

Answer 3

the size of storage required and how big the numbers can be

on SQL Server

tinyint 1 byte, 0 to 255

smallint 2 bytes, 2^15 (-32,768) to 2^15-1 (32,767)

int 4 bytes, -2^31 (-2,147,483,648) to 2^31-1 (2,147,483,647)

bigint 8 bytes, -2^63 (-9,223,372,036,854,775,808) to 2^63-1 (9,223,372,036,854,775,807)

you can store the number 1 in all 4, but a bigint will use 8 bytes while a tinyint will use 1 byte

Answer 4

Those seem to be MySQL data types.

According to the documentation they take:

1. tinyint = 1 byte
2. smallint = 2 bytes
3. mediumint = 3 bytes
4. int = 4 bytes
5. bigint = 8 bytes

And, naturally, accept increasingly larger ranges of numbers.