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MAX in WHERE not possible

You cannot use MAX() in a WHERE clause, instead use a subquery.

The ORDER BY is also unneeded, because we only select the maximum. So what to order, there is only one number (even if multiple entries with the same number).
Stefan Koch 12 年之前
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共有 1 個文件被更改,包括 1 次插入2 次删除
  1. 1 2
      documents/musterloesung-db-klausur-b/d3e.sql

+ 1 - 2
documents/musterloesung-db-klausur-b/d3e.sql

@@ -1,5 +1,4 @@
 SELECT berater_id, name, anzahl
     FROM Beratungsanzahl
     JOIN Berater ON Berater.berater_id = Beratungsanzahl.berater_id
-    WHERE anzahl = MAX(anzahl)
-    ORDER BY anzahl DESC
+    WHERE anzahl = (SELECT MAX(anzahl) FROM Beratungsanzahl)