UUID functions are used to generate UUID data (see UUID Type).
Description: Generates a UUID sequence number.
Return type: UUID
Example:
1 2 3 4 5 | SELECT uuid_generate_v1(); uuid_generate_v1 -------------------------------------- c71ceaca-a175-11e9-a920-797ff7000001 (1 row) |
The uuid_generate_v1 function generates UUIDs based on the time information, cluster node ID, and thread ID that generates the sequence. Each UUID is globally unique in a cluster, but there is a low probability that a UUID is duplicated among multiple clusters.
Description: Generate a sequence number that is the same as the sequence number generated by the Oracle sys_guid method.
Return type: text
Example:
1 2 3 4 5 | SELECT sys_guid(); sys_guid ---------------------------------- 4EBD3C74A17A11E9A1BF797FF7000001 (1 row) |
The data generation principle of the sys_guid function is the same as that of the uuid_generate_v1 function.