请教一句SQL
elxl 2004-11-30 11:04:30 TABLE T(A,B,C,D,E,F,G,H)
SELECT A,B,C,D,E,COUNT(*) NUMBER FROM T WHERE A='X' GROUP BY A,B,C HAVING COUNT(*) > 10
SELECT A,B,C,D,E,COUNT(C) NUMBER FROM T WHERE A='X' GROUP BY A,B,C HAVING COUNT(C) > 10
请问COUNT计算的是什么?这两个语句有什么不同吗?