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Restituisce un universal identifier "breve", un intero senza segno di 64 bit (invece della stringa di 128 bit restituita dalla funzione UUID()).

Il valore di UUID_SHORT() è sicuramente unico, finché sussistono le seguenti condizioni:

  • The server_id of the current host is unique among your set of master and slave servers
  • server_id is between 0 and 255
  • You don't set back your system time for your server between mysqld restarts
  • You do not invoke UUID_SHORT() on average more than 16 million times per second between mysqld restarts

The UUID_SHORT() return value is constructed this way:

  (server_id & 255) << 56
+ (server_startup_time_in_seconds << 24)
+ incremented_variable++;


MariaDB [(none)]> SELECT UUID_SHORT();
| UUID_SHORT()      |
| 21517162376069120 |

See also

  • UUID() ; Return full (128 bit) Universal Unique Identifier


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