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PHP的随机函数太占资源了

Discussion in '后端开发' started by laogui, Apr 16, 2009.

  1. laogui

    laogui Administrator
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    数据少还好，如果从几万内容里随机读取10条数据就慢了好几秒。

    有么有比rand好用的函数？
     
    #1 laogui, Apr 16, 2009
  2. qlq

    qlq Active Member

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    服务器的过
     
    #2 qlq, Apr 16, 2009
  3. lane

    lane New Member

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    mt_rand ?
     
    #3 lane, Apr 16, 2009
  4. Henry

    Henry New Member

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    那个rand是mysql的函数。 速度慢也是mysql 的慢。随机的时候要遍历整个数据库。肯定慢的。
     
    #4 Henry, Apr 16, 2009
  5. lane

    lane New Member

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    用PHP随机一个ID好了。然后直接取。
    先取最大的ID，然后从1到这个ID随机一个ID，如果不存在，重新随机一个。
    这样行不？
     
    #5 lane, Apr 16, 2009
  6. webren

    webren New Member

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    技术帖子哦.
     
    #6 webren, Apr 16, 2009
  7. notnull

    notnull New Member

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    你rand的范围指定了之后，不会慢的
    不会是先从mysql里取这个值的范围吧？？
     
    #7 notnull, Apr 16, 2009
  8. srsman

    srsman Active Member

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    楼上的女人是哪个？~
     
    #8 srsman, Apr 17, 2009
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