求SELECT語句的寫法，在線等待！！！

Question

select * from tb
where rowid in(select min(rowid) from tb group by A);

Answer 1

select A字段,B字段,C字段 from table where rowid in (select min(rowid) from table goup by A字段)

Answer 2

看时间上几乎和bzszp(www.bzszp.533.net)兄是同步. 呵呵...因为比bzszp(www.bzszp.533.net)多输入了几个字符.

Answer 3

min(rowid) 与 max(rowid)在速度上有差别吗？

Answer 4

我觉的有可能出现下面的情况：
ROWID                       A B                                        C
------------------ ---------- ---------------------------------------- ----
AAAGBaAABAAAITSAAC        123 120*300+50                               U
AAAGBaAABAAAITSAAB        123 100*300+50                               Y
AAAGBaAABAAAITSAAD        123 50*300+50                                R
AAAGBaAABAAAITSAAA        123 800*300+50                               I
AAAGBaAABAAAITSAAE        124 50*100                                   M
AAAGBaAABAAAITSAAF        124 100*100                                  B
AAAGBaAABAAAITSAAG        125 30*120+10                                O
AAAGBaAABAAAITSAAH        125 50*120                                   Y会不会出问题？