这个sql中的错误是什么

What is wrong with this query:

SELECT * FROM leaderboard WHERE ALREADYWON != '1' ORDER BY Score LIMIT 0,'$limit'

Code after it just throws errors:

Warning: Invalid argument supplied for foreach() in file ...

$limit definitely has a value, I'm echoing it out just before. I'm using Oracle.

Can anyone spot a syntax error?

ORACLE doesn't support LIMIT. I had to use this query

SELECT * FROM leaderboard 
WHERE rownum <= '$limit' 
AND ALREADYWON != '1' 
ORDER BY Score

Is ALREADYWON really a string? Shouldn't the comparison be using <> instead of != ?

Mixing PHP into a SQL statement is the problem. Everything after this...

SELECT * FROM leaderboard WHERE ALREADYWON != '1' ORDER BY Score

... will likely be the cause of your error

Also, its considered poor practice to 'SELECT *' for any table. You should be naming the columns explicitly.

After looking at some of your responses, it looks like you are trying to get TOP N records. For oracle, this is a few of the ways to get them (kind of dated, but should still work).

I'd say the != is wrong and should be <> to be a valid query. Also I don't know but '$limit' should perhaps be '".$limit."'. GL!

Oracle does not support the LIMIT keyword. The equivalent construct in Oracle would be something like

SELECT *
  FROM (SELECT *
          FROM leaderboard
         WHERE AlreadyWon != '1'
         ORDER BY score)
 WHERE rownum <= <<limit>>

Note that this is NOT equivalent to the query

SELECT *
  FROM leaderboard
 WHERE AlreadyWon != '1'
   AND rownum <= <<limit>>
 ORDER BY score

The first query gets the first <<limit>> rows based on the SCORE order. The second query gets an arbitrary set of <<limit>> rows and orders that arbitrary set because the ROWNUM filter is applied before the ORDER BY clause.

SELECT * FROM 
   (SELECT score, ROW_NUMBER() OVER (ORDER BY score) R FROM leaderboard WHERE alreadywon != 1)
   WHERE R BETWEEN 0 and '$Limit';

This will get you scores ordered but up to the limit you specified. Be careful though, as this is a candidate for SQL Injection. You might want to look into PHP parameterized queries instead.