Left join warning

[CathyVI]

Hi,

I did a left join of the two data and received this warning. Should I be concern about my outcome due to this warning or not. How can I rectify this issue for future codes.

/*perform left join*/
proc sql;
create table final_table_0607 as
select * from mth_0607 as x left join case_07 as y
on x.bene_id = y.bene_id;
quit;

>>>>>>>>>>>>>>>>>>>>>>

1 OPTIONS NONOTES NOSTIMER NOSOURCE NOSYNTAXCHECK;

72

73 proc sql;

74 create table final_table_0607 as

75 select * from mth_0607 as x left join case_07 as y

76 on x.bene_id = y.bene_id;

WARNING: Variable bene_id already exists on file WORK.FINAL_TABLE_0607.

NOTE: Table WORK.FINAL_TABLE_0607 created, with 14461320 rows and 19 columns.

[PaigeMiller · Accepted solution]

There is a variable named bene_id in both data sets in this left join. The final output data set will contain only one of these variables named bene_id, which IN THIS SPECIFIC CASE is not a problem because you left join on BENE_ID, and so the values of both variables of BENE_ID must match. (There can be other cases where the two variables have different values, and only one of those variables will wind up in the output data set)