Integer Data Type in SQLserver

In SQLServer, there are four types of integer data: bigint, int, smallint, and tinyint. They are distinguished by the number of digits they occupy. Bigint: 8 bytes, 64-bit. Integer Data int from-2 ^ 63 (-9223372036854775808) to 2 ^ 63-1 (9223372036854775807): 4 bytes, 32 bits. From-2 ^ 31 (-2,

In SQL Server, there are four types of integer data: bigint, int, smallint, and tinyint. They are distinguished by the number of digits they occupy. Bigint: 8 bytes, 64-bit. Integer Data int from-2 ^ 63 (-9223372036854775808) to 2 ^ 63-1 (9223372036854775807): 4 bytes, 32 bits. From-2 ^ 31 (-2,

Integer type in SQL ServerDataTypeThere are four types of bigint, int, smallint, and tinyint. They are distinguished by their digits.

Bigint: 8 bytes, 64-bit. Integer from-2 ^ 63 (-9223372036854775808) to 2 ^ 63-1 (9223372036854775807)Data

Int: 4 bytes, 32 bits. Integer from-2 ^ 31 (-2,147,483,648) to 2 ^ 31-1 (2,147,483,647)Data

Smallint: occupies 2 bytes, 16 bits. Integer from-2 ^ 15 (-32,768) to 2 ^ 15-1 (32,767)Data

Tinyint: takes 1 byte and 8 bits. Integer from 0 to 255Data

Note

Bigint is supported where integer values are supported.DataType. However, bigint is used in some special cases when the integer value exceeds int.DataTypeBigint can be used when the range is supported. In SQL Server, intDataTypeIs a major integer.DataType.

InDataTypeIn the priority table, bigint is located between smallmoney and int.

Only when the parameter expression is bigintDataTypeThe function returns bigint. SQL Server does not automatically add other integersDataType(Tinyint, smallint, and int) to bigint.

Summary

So select the most appropriateDataTypeIt is very important. For example, if you have 10 18 digits, they are all digital ID card numbers, and 10 15 digits are all digital ID card numbers. Let you find the 20 records at the fastest query speed. When designing this field, you should pay attention to the following points:

1. The fastest query speed is nothing more than int.TypeOfDataTo store the 20 ID card numbers. HoweverDataIt seems that only bigint meets the condition.

2. Why not use varchar or char. Directly save it as a string. The query speed of int must be faster than that of varchar and char.TypeOfDataIs the first choice, but there are several int types in sqlserver. Select the most appropriate one.