有关SQL问题，弄了半天了

Question

select carry_ls_sxb.CARRY_DL tt ,carry_ls_sxb.CARRY_DY mm ,carry_ls_Xxb.CARRY_DL dd ,carry_ls_Xxb.CARRY_DY cc ,carry_ls_Xxb.CARRY_wy bb from  carry_ls_sxb,CARRY_LS_XXB 这个SQL 语句每个 表里只有12条记录
为什么我一取就取出了144条记录呢
怎么能控制就取12条记录呢?? 
这些是144条记录 同一条记录显示了12次怎么才能一条记录就显示一次呢
55.0 220.0 55.0 219.0 2.3999999999999999
58.0 220.0 55.0 219.0 2.3999999999999999
55.0 220.0 55.0 219.0 2.3999999999999999
49.0 220.0 55.0 219.0 2.3999999999999999
55.0 220.0 55.0 219.0 2.3999999999999999
47.0 220.0 55.0 219.0 2.3999999999999999
55.0 220.0 55.0 219.0 2.3999999999999999
53.0 220.0 55.0 219.0 2.3999999999999999
55.0 220.0 55.0 219.0 2.3999999999999999
55.0 220.0 55.0 219.0 2.3999999999999999
55.0 220.0 55.0 219.0 2.3999999999999999
55.0 220.0 55.0 219.0 2.3999999999999999
55.0 220.0 44.0 220.0 2.6000000000000001
58.0 220.0 44.0 220.0 2.6000000000000001
55.0 220.0 44.0 220.0 2.6000000000000001
49.0 220.0 44.0 220.0 2.6000000000000001
55.0 220.0 44.0 220.0 2.6000000000000001
47.0 220.0 44.0 220.0 2.6000000000000001
55.0 220.0 44.0 220.0 2.6000000000000001
53.0 220.0 44.0 220.0 2.6000000000000001
55.0 220.0 44.0 220.0 2.6000000000000001
55.0 220.0 44.0 220.0 2.6000000000000001
55.0 220.0 44.0 220.0 2.6000000000000001
55.0 220.0 44.0 220.0 2.6000000000000001
55.0 220.0 55.0 220.0 3.5
58.0 220.0 55.0 220.0 3.5
55.0 220.0 55.0 220.0 3.5
49.0 220.0 55.0 220.0 3.5
55.0 220.0 55.0 220.0 3.5
47.0 220.0 55.0 220.0 3.5
55.0 220.0 55.0 220.0 3.5
53.0 220.0 55.0 220.0 3.5
55.0 220.0 55.0 220.0 3.5
55.0 220.0 55.0 220.0 3.5
55.0 220.0 55.0 220.0 3.5
55.0 220.0 55.0 220.0 3.5
55.0 220.0 54.0 221.0 4.0
58.0 220.0 54.0 221.0 4.0
55.0 220.0 54.0 221.0 4.0
49.0 220.0 54.0 221.0 4.0
55.0 220.0 54.0 221.0 4.0
47.0 220.0 54.0 221.0 4.0
55.0 220.0 54.0 221.0 4.0
53.0 220.0 54.0 221.0 4.0
55.0 220.0 54.0 221.0 4.0
55.0 220.0 54.0 221.0 4.0
55.0 220.0 54.0 221.0 4.0
55.0 220.0 54.0 221.0 4.0
55.0 220.0 55.0 215.0 4.5
58.0 220.0 55.0 215.0 4.5
55.0 220.0 55.0 215.0 4.5
49.0 220.0 55.0 215.0 4.5
55.0 220.0 55.0 215.0 4.5
47.0 220.0 55.0 215.0 4.5
55.0 220.0 55.0 215.0 4.5
53.0 220.0 55.0 215.0 4.5
55.0 220.0 55.0 215.0 4.5
55.0 220.0 55.0 215.0 4.5
55.0 220.0 55.0 215.0 4.5
55.0 220.0 55.0 215.0 4.5
55.0 220.0 52.0 220.0 4.5999999999999996
58.0 220.0 52.0 220.0 4.5999999999999996
55.0 220.0 52.0 220.0 4.5999999999999996
49.0 220.0 52.0 220.0 4.5999999999999996
55.0 220.0 52.0 220.0 4.5999999999999996
47.0 220.0 52.0 220.0 4.5999999999999996
55.0 220.0 52.0 220.0 4.5999999999999996
53.0 220.0 52.0 220.0 4.5999999999999996
55.0 220.0 52.0 220.0 4.5999999999999996
55.0 220.0 52.0 220.0 4.5999999999999996
55.0 220.0 52.0 220.0 4.5999999999999996
55.0 220.0 52.0 220.0 4.5999999999999996
55.0 220.0 55.0 220.0 4.7000000000000002
58.0 220.0 55.0 220.0 4.7000000000000002
55.0 220.0 55.0 220.0 4.7000000000000002
49.0 220.0 55.0 220.0 4.7000000000000002
55.0 220.0 55.0 220.0 4.7000000000000002
47.0 220.0 55.0 220.0 4.7000000000000002
55.0 220.0 55.0 220.0 4.7000000000000002
53.0 220.0 55.0 220.0 4.7000000000000002
55.0 220.0 55.0 220.0 4.7000000000000002
55.0 220.0 55.0 220.0 4.7000000000000002
55.0 220.0 55.0 220.0 4.7000000000000002
55.0 220.0 55.0 220.0 4.7000000000000002
55.0 220.0 51.0 220.0 5.0
58.0 220.0 51.0 220.0 5.0
55.0 220.0 51.0 220.0 5.0
49.0 220.0 51.0 220.0 5.0
55.0 220.0 51.0 220.0 5.0
47.0 220.0 51.0 220.0 5.0
55.0 220.0 51.0 220.0 5.0
53.0 220.0 51.0 220.0 5.0
55.0 220.0 51.0 220.0 5.0
55.0 220.0 51.0 220.0 5.0
55.0 220.0 51.0 220.0 5.0
55.0 220.0 51.0 220.0 5.0
55.0 220.0 55.0 219.5 5.5
58.0 220.0 55.0 219.5 5.5
55.0 220.0 55.0 219.5 5.5
49.0 220.0 55.0 219.5 5.5
55.0 220.0 55.0 219.5 5.5
47.0 220.0 55.0 219.5 5.5
55.0 220.0 55.0 219.5 5.5
53.0 220.0 55.0 219.5 5.5
55.0 220.0 55.0 219.5 5.5
55.0 220.0 55.0 219.5 5.5
55.0 220.0 55.0 219.5 5.5
55.0 220.0 55.0 219.5 5.5
55.0 220.0 49.0 220.0 5.7999999999999998
58.0 220.0 49.0 220.0 5.7999999999999998
55.0 220.0 49.0 220.0 5.7999999999999998
49.0 220.0 49.0 220.0 5.7999999999999998
55.0 220.0 49.0 220.0 5.7999999999999998
47.0 220.0 49.0 220.0 5.7999999999999998
55.0 220.0 49.0 220.0 5.7999999999999998
53.0 220.0 49.0 220.0 5.7999999999999998
55.0 220.0 49.0 220.0 5.7999999999999998
55.0 220.0 49.0 220.0 5.7999999999999998
55.0 220.0 49.0 220.0 5.7999999999999998
55.0 220.0 49.0 220.0 5.7999999999999998
55.0 220.0 60.0 220.0 5.9000000000000004
58.0 220.0 60.0 220.0 5.9000000000000004
55.0 220.0 60.0 220.0 5.9000000000000004
49.0 220.0 60.0 220.0 5.9000000000000004
55.0 220.0 60.0 220.0 5.9000000000000004
47.0 220.0 60.0 220.0 5.9000000000000004
55.0 220.0 60.0 220.0 5.9000000000000004
53.0 220.0 60.0 220.0 5.9000000000000004
55.0 220.0 60.0 220.0 5.9000000000000004
55.0 220.0 60.0 220.0 5.9000000000000004
55.0 220.0 60.0 220.0 5.9000000000000004
55.0 220.0 60.0 220.0 5.9000000000000004
55.0 220.0 55.0 223.0 6.0
58.0 220.0 55.0 223.0 6.0
55.0 220.0 55.0 223.0 6.0
49.0 220.0 55.0 223.0 6.0
55.0 220.0 55.0 223.0 6.0
47.0 220.0 55.0 223.0 6.0
55.0 220.0 55.0 223.0 6.0
53.0 220.0 55.0 223.0 6.0
55.0 220.0 55.0 223.0 6.0
55.0 220.0 55.0 223.0 6.0
55.0 220.0 55.0 223.0 6.0
55.0 220.0 55.0 223.0 6.0

Answer 1

select distinct 
carry_ls_sxb.CARRY_DL tt ,carry_ls_sxb.CARRY_DY mm ,carry_ls_Xxb.CARRY_DL dd ,carry_ls_Xxb.CARRY_DY cc ,carry_ls_Xxb.CARRY_wy bb from  carry_ls_sxb,CARRY_LS_XXB ...

Answer 2

改成下面的：
select carry_ls_sxb.CARRY_DL tt ,carry_ls_sxb.CARRY_DY mm ,carry_ls_Xxb.CARRY_DL dd ,carry_ls_Xxb.CARRY_DY cc ,carry_ls_Xxb.CARRY_wy bb from  carry_ls_sxb,CARRY_LS_XXB 
where carry_ls_sxb.CARRY_DL =carry_ls_Xxb.CARRY_DL

Answer 3

我同意huailairen(流浪猫)的看法。
如果没有限制条件查到的结果就是两个表里记录的叉乘结果或着用distinct的关键字去掉重复的记录。