When the integer value is beyond the range supported by the int data type, SQL Server will use the bigint data type. For compatibility reasons, int data type is still the main integer data type in Microsoft SQL Server 2005.

Functions, statements and system stored procedures that accept int expressions as their parameters will not change unless explicitly stated, so implicit conversion of bigint expressions into these parameters is not supported.

Therefore, when the bigint value is within the range supported by the int data type, SQL Server will implicitly convert bigint to int. If the bigint expression contains values beyond the range supported by the int data type, a conversion error will occur at run time.

The range of values represented by int data type is -2 3 1 to 2 3 1- 1, that is to say, -2,147,483,648 to 2,147,483, can be represented by int data type. The int type occupies four bytes of storage space.

Extended data

Matters needing attention

In the data type priority table, bigint data type is above int and below smallmoney. SQL Server cannot automatically convert int data into bigint data. If the parameter expression of a function is of type bigint, the function can only return data of type bigint.

Functions that use bigint data type include AVG, upper limit, lower limit, maximum value, minimum value, rounding, summation, etc.

You can use bigint data types in all syntax positions of specified integer data: ALTER PROCEDURE, ALTER TABLE, CREATE PROCEDURE, CREATE TABLE and DECLARE variables.

You can get the information of bigint column in the directory component of SQL Server.

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