ABerglundKey1
.CHECKSUM
function returns the checksum value computed over a table row, or over an expression list. Use CHECKSUM
to build hash indexes.CHECKSUM
returns an error if any column has a noncomparable data type. Noncomparable data types include:CHECKSUM
computes a hash value, called the checksum, over its argument list. Use this hash value to build hash indexes. A hash index will result if the CHECKSUM
function has column arguments, and an index is built over the computed CHECKSUM
value. This can be used for equality searches over the columns.CHECKSUM
function satisfies hash function properties: CHECKSUM
applied over any two lists of expressions will return the same value, if the corresponding elements of the two lists have the same data type, and if those corresponding elements have equality when compared using the equals (=) operator. Null values of a specified type are defined to compare as equal for CHECKSUM
function purposes. If at least one of the values in the expression list changes, the list checksum will probably change. However, this is not guaranteed.Therefore, to detect whether values have changed, we recommend use of CHECKSUM
only if your application can tolerate an occasional missed change. Otherwise, consider using HASHBYTES
instead. With a specified MD5 hash algorithm, the probability that HASHBYTES
will return the same result, for two different inputs, is much lower compared to CHECKSUM
. Imovie templates free download mac.CHECKSUM
value. The order of columns used for CHECKSUM(*)
is the order of columns specified in the table or view definition. This includes computed columns.CHECKSUM
value depends on the collation. The same value stored with a different collation will return a different CHECKSUM
value.CHECKSUM ()
does not guarantee unique results.CHECKSUM
to build hash indexes.ProductName
value will propagate to the checksum column. Alternatively, we could build an index directly on the column we want to index. However, for long key values, a regular index will probably not perform as well as a checksum index.