data b;
merge b a;
by id;
方法很多，用update代替merge也可以，但是merge比较简单

WARNING: Multiple lengths were specified for the variable name by input data set(s). This may cause truncation of data.
WARNING: The MASTER data set contains more than one observation for a BY group.
。。。。。
ERROR: BY variables are not properly sorted on data set MYDATA.CN00
NOTE: The SAS System stopped processing this step because of errors.
NOTE: There were 6833 observations read from the data set MYDATA.IE_P_JAP.
NOTE: There were 59622 observations read from the data set MYDATA.CN00.
WARNING: The data set MYDATA.IE_P_JAP may be incomplete.  When this step was stopped there were 7472 observations and 120 variables.
WARNING: Data set MYDATA.IE_P_JAP was not replaced because this step was stopped.
NOTE: DATA statement used (Total process time):
      real time           0.25 seconds
      cpu time            0.21 seconds
失败。。难道是因为数据集格式不一样不能merge吗，求教

你b中的name是numeric还是character？

b中的是$32.
a中的是$200.

而且我直线更新name，这样会不会把其他的变量也改变了？