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The RAND () Optimization Method for MySQL optimization and the rand Method for mysql Optimization As we all know, in MySQL, if order by rand () is used directly, the efficiency is very poor because it will be executed multiple times. In fact, this

This article mainly introduces the RAND () optimization method for MySQL optimization. This article analyzes several optimization methods for RAND () in Mysql in detail, and finally draws a conclusion, if you want to directly order by rand () in

This paper compares and analyzes the performance problem of random function Mt_rand () and Rand () in PHP. Share to everyone for your reference. The specific analysis is as follows: The Mt_rand () and Rand () functions in PHP can randomly generate

[MySQL optimization case] series-RAND () optimization we all know that in MySQL, if order by rand () is used directly, the efficiency is very poor because it will be executed multiple times. In fact, this is also true if the equivalent query uses

As we all know, in MySQL, if direct order by RAND (), the efficiency is very poor, because it will be executed multiple times. In fact, if the equivalent query is also in RAND (), let's take a look at the different execution plans and execution time

As we all know, in MySQL, if the direct ORDER by RAND (), the efficiency is very poor, because it will be executed multiple times. In fact, if the equivalent query is also used with RAND (), let's take a look at the different execution plans and

As we all know, in MySQL, if direct order by RAND (), the efficiency is very poor, because it will be executed multiple times. In fact, if the equivalent query is also in RAND (), let's take a look at the different execution plans and execution time

Example 1. Mt_rand () example The code is as follows Copy Code Echo Mt_rand (). "N";Echo Mt_rand (). "N";Echo Mt_rand (5, 15);?>The output of the example above is similar to the following:160471601414786132786

This paper compares and analyzes the performance problem of random function Mt_rand () and Rand () in PHP. Share to everyone for your reference. The specific analysis is as follows: in PHP Mt_rand () and Rand () functions are randomly generated a

How to write a statement can update hundreds of MySQL data! Need to test MySQL database, there is a database of tens of thousands of data, how to write a PHP file each time update hundreds of information, I am writing a cycle update a message, so I