左连接返回空格

示例代码未演示此问题。

实际上,缺少的值 join1-join3 当实际business\u lines值为 'Retail' 或 Business . 结果是零售业为3x1行,商业为2x1行。

如果左表中的联接键在右表中没有相应的匹配项,则会出现缺少的值。这个罐子 显得 如果变量已格式化,则在SAS中发生。

假设business\u line是一个带格式值的整数

proc format;
  value line
    101 = 'Retail'
    102 = 'Retail'
    103 = 'Retail'
    201 = 'Business'
    202 = 'Business'
  ;

使用格式化的business\u行更新数据

data joined;
input Business_Line;
format Business_Line line.;
datalines;
101
102
102
201
202
run;    

data assumptions;
input Business_Line Join1 Join2 Join3;
format Business_Line line.;
datalines;
101 10 10 10
201 20 10  5
run;

具有一些不匹配的基础值的联接

proc sql;
create table joined2 as
select a.*
      ,b.Join1
      ,b.Join2
      ,b.Join3
from joined as a
left join Assumptions as b
on a.Business_Line = b.Business_Line;
quit;

options nocenter; ods listing;
proc print data=joined2;
run;

结果显示缺少值

       Business_
Obs      Line       Join1    Join2    Join3

 1     Retail         10       10       10
 2     Retail          .        .        .
 3     Retail          .        .        .
 4     Business       20       10        5
 5     Business        .        .        .