![]() If (!isset($reported) & $numberOfLoops / 10 > 0. If inserted row count equal to 0, go to point 1.Insert row with generated number as user_id MySQL MySQL MySQL MD5()RAND() SUBSTR() SELECTSUBSTR(MD5(RAND()),1,8)ASRandomString +-+ RandomString +-+ 7d192f5f +-+ 1 row in set (0.Generate random number for user_id (UNIQUE).How about this approach ( PHP and MySQL): ![]() This approach guarantees uniqueness and takes any processing load away from the insert transaction and into the batch routine, where it does not affect the user. (If I ever get 10000 orders in one day I'll have a problem - but that would be a good problem to have!) I have a routine that runs every night which pre-loads this table with enough unique_id rows to more than cover the orders that might be inserted in the next 24 hours. Then I have another table - unique_ids with (order_id, unique_id). The user does not need to see this internal id. I’m aware it’s not the most random of generators but for url hashes etc, it works well. Here, we will learn about the easiest and most efficient methods to generate random and unique strings in MySQL. This id is generated on the fly when the user enters the order, incrementally 1,2,3 etc forever. The code below allows you to generate a different string for each row affected by the update and choose the random string’s length from 1 to 32 character. There is no built-in method to generate random strings in MySQL, but there are many other ways that we can get an advantage to meet the requirements. What I do is pre-generate unique id's for future use, that way I can take my own sweet time and absolutely guarantee they are unique, and there's no processing to be done at the time of the insert.įor example I have an orders table with order_id in it. Now, you have the function already to generate random string its time to call this function and display the result. The generated data can also be used for random file names or random IDs in tests. You can also generate random numbers and random text snippets from a custom alphabet. If HEX is enough, here is a short solution: SELECT HEX (RAND ()0xFFFFFFFF) It might be less than 8 chars, but you can add for 'F's and use LEFT () to be safe. My point is that you do not need to generate these unique id's at the time of creating your rows, because they are essentially independent of the data being inserted. You can independently generate random strings of any length made out of lowercase or uppercase characters, including single-character strings. How you generate the unique_ids is a useful question - but you seem to be making a counter productive assumption about when you generate them! ![]()
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