This ordering includes computed columns.īINARY_CHECKSUM and CHECKSUM return different values for the string data types, where locale can cause strings with different representation to compare as equal. The order of columns used for BINARY_CHECKSUM(*) is the order of columns specified in the table or view definition. They can be used to compute a checksum value on a list of expressions, and the order of expressions affects the resultant value. For this definition, null values of a specified type are considered to have the same byte representation.īINARY_CHECKSUM and CHECKSUM are similar functions. BINARY_CHECKSUM applied over any two lists of expressions returns the same value if the corresponding elements of the two lists have the same type and byte representation. With a specified MD5 hash algorithm, the probability that HASHBYTES will return the same result, for two different inputs, is much lower than BINARY_CHECKSUM.īINARY_CHECKSUM can operate over a list of expressions, and it returns the same value for a specified list. Otherwise, consider using HASHBYTES instead. However, this change isn't guaranteed, and so to detect whether values have changed, we recommend use of BINARY_CHECKSUM only if your application can tolerate an occasional missed change. If at least one of the values in the expression list changes, the expression checksum can also change. For this definition, we say that null values, of a specified type, compare as equal values.
BINARY_CHECKSUM satisfies the properties of a hash function: when applied over any two lists of expressions, returns the same value if the corresponding elements of the two lists have the same type and are equal when compared using the equals (=) operator. Return TypesīINARY_CHECKSUM(*), computed on any row of a table, returns the same value as long the row isn't modified later. BINARY_CHECKSUM ignores expressions of noncomparable data types in its computation. Noncomparable data types includeĪnd noncomparable common language runtime (CLR) user-defined types.Īn expression of any type. BINARY_CHECKSUM ignores columns of noncomparable data types in its computation. Specifies that the computation covers all the table columns. To view Transact-SQL syntax for SQL Server 2014 and earlier, see Previous versions documentation.
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