mysql

http://blog.naver.com/tomatogun/100040675312

MySQL:
SELECT column FROM table ORDER BY RAND() LIMIT 1

PostgreSQL:
SELECT column FROM table ORDER BY RANDOM() LIMIT 1

Microsoft SQL Server:
SELECT TOP 1 column FROM table ORDER BY NEWID()

IBM DB2:
SELECT column FROM table ORDER BY RAND() FETCH FIRST 1 ROWS ONLY

Oracle:
SELECT column FROM ( SELECT column FROM table ORDER BY dbms_random.value ) WHERE rownum = 1

DBMS마다 다 다르니 ;;

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