如何在MySQL中生成UUIDv4？

如何在MySQL中生成UUIDv4？

我花了很多时间寻找解决方案，并提出了以下mysql函数，该函数使用标准MySQL函数生成一个随机UUID（即UUIDv4）。我正在回答我自己的问题，以期分享它，希望对大家有用。

-- Change delimiter so that the function body doesn't end the function declarationDELIMITER //CREATE FUNCTION uuid_v4()    RETURNS CHAr(36)BEGIN    -- Generate 8 2-byte strings that we will combine into a UUIDv4    SET @h1 = LPAd(HEx(FLOOR(RAND() * 0xffff)), 4, '0');    SET @h2 = LPAd(HEx(FLOOR(RAND() * 0xffff)), 4, '0');    SET @h3 = LPAd(HEx(FLOOR(RAND() * 0xffff)), 4, '0');    SET @h6 = LPAd(HEx(FLOOR(RAND() * 0xffff)), 4, '0');    SET @h7 = LPAd(HEx(FLOOR(RAND() * 0xffff)), 4, '0');    SET @h8 = LPAd(HEx(FLOOR(RAND() * 0xffff)), 4, '0');    -- 4th section will start with a 4 indicating the version    SET @h4 = CONCAt('4', LPAd(HEx(FLOOR(RAND() * 0x0fff)), 3, '0'));    -- 5th section first half-byte can only be 8, 9 A or B    SET @h5 = CONCAt(HEx(FLOOR(RAND() * 4 + 8)),     LPAd(HEx(FLOOR(RAND() * 0x0fff)), 3, '0'));    -- Build the complete UUID    RETURN LOWER(CONCAt(        @h1, @h2, '-', @h3, '-', @h4, '-', @h5, '-', @h6, @h7, @h8    ));END//-- Switch back the delimiterDELIMITER ;

注意：所使用的伪随机数生成（MySQL’s

RAND

）在密码上不是安全的，因此存在一些偏差，可能会增加冲突风险。