crc64

NAME

crc64(): Return a 64 bit CRC of given input, as unsigned big integer.

TYPE

Function

DESCRIPTION

This function complements MySQL's crc32() function, which results with poor distribution on large number of values. The crc64() algorithm relies on MD5 as underlying mechanism.

While input data is textual, any type can be passed in, due to SQL's implicit casting nature.

This code is based on the idea presented in the book High Performance MySQL, 2nd Edition, By Baron Schwartz et al., published by O'REILLY

SYNOPSIS

crc64(data LONGTEXT CHARSET utf8) 
  RETURNS BIGINT UNSIGNED

Input:

  • data: data to run CRC on. This can be textual, numeric, temporal, or any other type that can be implicitly converted to TEXT.

EXAMPLES

Calculate 64 bit CRC for some text: 

mysql> SELECT common_schema.crc64('mysql') AS crc64;
+---------------------+
| crc64               |
+---------------------+
| 9350511318824990686 |
+---------------------+

ENVIRONMENT

MySQL 5.1 or newer

SEE ALSO

query_checksum(), random_hash()

AUTHOR

Shlomi Noach
 
common_schema documentation