各数据库 uuid 函数

数据库	uuid
PostgreSQL	replace(gen_random_uuid()::text, '-', '')
MySQL	replace(uuid(), '-', '')
Oracle	lower(rawtohex(sys_guid()))
SQL Server	replace(newid(), '-', '')
DB2	SELECT LOWER(hex(RAND()) || hex(RAND())) AS uuid FROM "SYSIBM".sysdummy1