Subtracts two numbers and sets a value to the result of the operation. For example, if a variable @x equals 35, then @x -= 2 takes the original value of @x, subtracts 2 and sets @x to that new value (33).
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expression
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Is any valid expression of any one of the data types in the numeric category except the bit data type.
For more information, see - (Subtract) (Transact-SQL).
Returns the data type of the argument with the higher precedence. For more information, see Data Type Precedence (Transact-SQL).
Reference
Compound Operators (Transact-SQL)
Expressions (Transact-SQL)
Operators (Transact-SQL)
Help and Information
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