MySQL Random Data Selection from Table

In this article, introduce how to extract random data effectively from MySQL table. Many solutions in stackoverflow are very slow or inefficient. Select Random Id SELECT ROUND(RAND()*(SELECT COUNT(*) FROM table_name)) AS id; At first, we can create random id which is in your table table_name. Select Random Id List And then, by using this, SELECT ROUND(RAND()*(SELECT COUNT(*) FROM table_name)) AS id FROM table_name LIMIT 100; We can get 100 random id from this SQL. If you want to get ...

MySQL 명령어 정리

MySQL 접속 # mysql -u username -p   Database 관리 mysql> SHOW databases; mysql> CREATE DATABASE dbname; mysql> DROP DATABASE [IF EXISTS] dbname; mysql> USE dbname;   MySQL 사용자 추가 mysql> GRANT ALL PRIVILEGES ON dbname.* TO username@localhost IDENTIFIED BY 'password';   Table 관리 mysql> USE dbname; mysql> SHOW tables; mysql> CREATE TABLE tablename(col1 type, col2 type, ...); mysql> EXPLAIN tablename; mysql> DESCRIBE tablename; mysql> ...