Caché MultiValue Basic Reference
CHECKSUM
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Returns a checksum number for a string.
Synopsis
CHECKSUM(string)
Arguments
string An expression that resolves to a string.
Description
The CHECKSUM function generates a cyclic redundancy code (also called a checksum) corresponding to string. It returns this checksum as a positive 5-digit integer. A checksum can be used to determine if data has been modified or if it was incompletely transmitted. CHECKSUM uses an 8-bit byte sum mode to calculate the checksum.
CHECKSUM returns the same checksum number for a numeric and the corresponding numeric string. However, numerics are converted to canonical form before checksum processing, whereas numeric strings are not converted to canonical form. Canonical and non-canonical forms of the same number have different checksums.
All string and numeric values, including zero, return a 5-digit checksum. However, if string is a null string a checksum of 0 is returned.
Examples
The following examples all return the same checksum:
PRINT CHECKSUM(123.4)
PRINT CHECKSUM("123.4")
PRINT CHECKSUM(+00123.400)
The following examples do not return the same checksum:
PRINT CHECKSUM(123.400)
PRINT CHECKSUM("123.400")
See Also