我有三个关系a，b，c
A(Ka1,Ka2,Ka3)
B(Kb1,Kb2)
C(Kc1,Kc2)我想这样加入
joined_data = JOIN B by Kb1 RIGHT, A by Ka2;
joined_data = JOIN C by Kb2 RIGHT, joined_data by Ka3;所以我最终得到这样的输出
joined_data(Ka1,Ka3,Ka2,Kb2,Kc2)有没有更好/更有效的方法？
我有三个关系a，b，c
A(Ka1,Ka2,Ka3)
B(Kb1,Kb2)
C(Kc1,Kc2)我想这样加入
joined_data = JOIN B by Kb1 RIGHT, A by Ka2;
joined_data = JOIN C by Kb2 RIGHT, joined_data by Ka3;所以我最终得到这样的输出
joined_data(Ka1,Ka3,Ka2,Kb2,Kc2)有没有更好/更有效的方法？
暂无答案！
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