douqi0090 2012-03-24 21:00
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MySQL中的IF语句,使用THEN和ELSE

I am testing out IF statements in MySQL for the first time and I am coming across an error.

I am trying to firstly, find out how many rows are in the table, then depending on whether the count is less than or equal to five, return all of the rows in the table, or if it isn't, return all posts in the range used within the LIMIT clause.

The error I am receiving is as follows;

You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'IF SELECT COUNT(*) FROM Posts <= 5 THEN SELECT * FROM Posts ELSE SELECT * FR' at line 1

Please can you tell me where I am going wrong?

Max.

$query = mysql_query(
    "IF SELECT COUNT(*) FROM `Posts` <= 5 
     THEN 
         SELECT * FROM `Posts` 
     ELSE 
         SELECT * FROM `Posts` LIMIT $from, $limit") 
     or die(mysql_error());
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2条回答 默认 最新

  • douci6541 2012-03-24 21:05
    关注

    you don't need to do this. Mysql handles this automatically, just use

    $query = "SELECT * FROM `Posts` LIMIT $from, $limit";
    
    本回答被题主选为最佳回答 , 对您是否有帮助呢?
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