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          sql隨機(jī)函數(shù)在各種數(shù)據(jù)庫(kù)的使用

          sql隨機(jī)函數(shù)在各種數(shù)據(jù)庫(kù)的使用(轉(zhuǎn))

          There are lots of ways to select a random record or row from a database table. Here are some example SQL statements that don't require additional application logic, but each database server requires different SQL syntax.

          Select a random row with MySQL:

          SELECT column FROM table
                                              ORDER BY RAND()
                                              LIMIT 1
                                              

          Select a random row with PostgreSQL:

          SELECT column FROM table
                                              ORDER BY RANDOM()
                                              LIMIT 1
                                              

          Select a random row with Microsoft SQL Server:

          SELECT TOP 1 column FROM table
                                              ORDER BY NEWID()
                                              

          Select a random row with IBM DB2

          SELECT column, RAND() as IDX
                                              FROM table
                                              ORDER BY IDX FETCH FIRST 1 ROWS ONLY
                                              

          Thanks Tim

          Select a random record with Oracle:

          SELECT id FROM
                  ( SELECT id from  tbl_lib_question
                  ORDER BY dbms_random.value )
                  WHERE rownum <20

          Thanks Mark Murphy

          Feel free to post other example, variations, and SQL statements for other database servers in the comments.

          posted on 2009-03-26 22:21 強(qiáng)強(qiáng) 閱讀(581) 評(píng)論(0)  編輯  收藏 所屬分類: Oracle數(shù)據(jù)庫(kù)

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