產生唯一的13位數：MySQL中的方法與技巧-PHP中文網路問答

大家好，我一整天都在嘗試為資料庫中的現有產品產生唯一的 13 個數字。每個產品都必須有EAN13 條碼。我嘗試了網路上的許多例子，但沒有一個給我帶來好的結果。有人有辦法解決這個問題嗎？

我嘗試了這個，但沒有任何效果

select cast( (@n := (13*@n + 100) % 899999999981)+1e12 as char(15)) as num from (select @n := floor(rand() * 10e14) ) init, (select 1 union select 2) m01, (select 1 union select 2) m02, (select 1 union select 2) m03, (select 1 union select 2) m04, (select 1 union select 2) m05, (select 1 union select 2) m06, (select 1 union select 2) m07, (select 1 union select 2) m08, (select 1 union select 2) m09, (select 1 union select 2) m10, (select 1 union select 2) m11, (select 1 union select 2) m12, (select 1 union select 2) m13, (select 1 union select 2) m14, (select 1 union select 2) m15, (select 1 union select 2) m16, (select 1 union select 2) m17, (select 1 union select 2) m18, (select 1 union select 2) m19, (select 1 union select 2) m20, (select 1 union select 2) m21, (select 1 union select 2) m22 limit 5;

我現在如何使用上面的程式碼更新現有表中的所有 12000 行。我嘗試 UPDATE，但當我嘗試混合 UPDATE 和 CAST 時出現錯誤

產品表結構為：

productid INT(11) productName Varchar(225) barcode INT(13)

INSERT INTO unique_numbers (barcode) SELECT CAST( (@n := (13*@n + 100) % 899999999981)+1e12 as char(15)) as num FROM (SELECT @n := floor(rand() * 10e14) ) init, (SELECT 1 UNION SELECT 2) m01, (SELECT 1 UNION SELECT 2) m02, (SELECT 1 UNION SELECT 2) m03, (SELECT 1 UNION SELECT 2) m04, (SELECT 1 UNION SELECT 2) m05, (SELECT 1 UNION SELECT 2) m06, (SELECT 1 UNION SELECT 2) m07, (SELECT 1 UNION SELECT 2) m08, (SELECT 1 UNION SELECT 2) m09, (SELECT 1 UNION SELECT 2) m10, (SELECT 1 UNION SELECT 2) m11, (SELECT 1 UNION SELECT 2) m12, (SELECT 1 UNION SELECT 2) m13, (SELECT 1 UNION SELECT 2) m14, (SELECT 1 UNION SELECT 2) m15, (SELECT 1 UNION SELECT 2) m16, (SELECT 1 UNION SELECT 2) m17, (SELECT 1 UNION SELECT 2) m18, (SELECT 1 UNION SELECT 2) m19, (SELECT 1 UNION SELECT 2) m20, (SELECT 1 UNION SELECT 2) m21, (SELECT 1 UNION SELECT 2) m22 LIMIT 12000;