Data Type Precedence
When two expressions of different data types are combined by an operator, the data type precedence rules specify which data type is converted to the other. The data type with the lower precedence is converted to the data type with the higher precedence. If the conversion is not a supported implicit conversion, an error is returned. When both operand expressions have the same data type, the result of the operation has that data type.
This is the precedence order for the Microsoft® SQL Server™ 2000 data types:
- sql_variant (highest)
- binary (lowest)