MD5
Overview
The MD5 function computes the MD5 hash of a given string. MD5 is a widely used hash function that maps data of arbitrary length to a fixed-length (128-bit) digest. MD5 digests are commonly used to verify data integrity.
Syntax
md5(expr)
Parameters
expr: The string, character, or variable-length character data type for which you want to compute the MD5 value.
Return Value
Returns a string representing the computed MD5 hash.
Examples
- Compute the MD5 of a simple string:
SELECT md5('hello') as res;
+----------------------------------+
| res |
+----------------------------------+
| 5d41402abc4b2a76b9719d911017c592 |
+----------------------------------+
- Compute the MD5 of a string containing special characters:
SELECT md5('Hello, World!') as res;
+----------------------------------+
| res |
+----------------------------------+
| 65a8e27d8879283831b664bd8b7f0ad4 |
+----------------------------------+
- Compute the MD5 of a Chinese string:
SELECT md5('你好,世界!') as res;
+----------------------------------+
| res |
+----------------------------------+
| 5082079d92a8ef985f59e001d445ff20 |
+----------------------------------+
- Compute the MD5 of a numeric string:
SELECT md5('12345');
+----------------------------------+
| res |
+----------------------------------+
| 827ccb0eea8a706c4c34a16891f84e7b |
+----------------------------------+
Notes
- MD5 hashes are irreversible — you cannot derive the original data from the hash value.