If you just run the code

select * from a ,c where a.a=c.a;

you will see in the result two columns with the same name. Like wise for the second SELECT. That is the ambiguity.

Try

create table test as select a.* from a ,c where a.a=c.a outer union corr select b.* from b ,c where b.a=c.a;

On Fri, 14 Mar 2003 06:44:25 -0800, peter <fjo2222222@HOTMAIL.COM> wrote:

>I have written many, many programs in sas version 6.12 containing >sql-code like : >proc sql; > create table test as > select * from a ,c > where a.a=c.a > outer union corr > select * from b ,c > where b.a=c.a; >and there was never a problem concatenating two queries this way, but >... in verion 8.2 I get the errors below. > >Please somebody tell me : What is wrong? > > >5 data a; >6 a=0; b=2; output; >7 a=1; b=3; output; >8 a=2; b=2; output; >9 a=3; b=2; output; > >NOTE: The data set WORK.A has 4 observations and 2 variables. >NOTE: DATA statement used: > real time 0.00 seconds > cpu time 0.00 seconds > > >10 data b; >11 a=0; c=2; output; >12 a=1; c=5; output; >13 a=2; c=67; output; >14 a=5; c=28; output; > >NOTE: The data set WORK.B has 4 observations and 2 variables. >NOTE: DATA statement used: > real time 0.02 seconds > cpu time 0.01 seconds > > >15 data c; >16 a=0; output; >17 a=2; output; >18 a=3; output; >19 a=5; output; >20 a=6; output; >21 run; > >NOTE: The data set WORK.C has 5 observations and 1 variables. >NOTE: DATA statement used: > real time 0.01 seconds > cpu time 0.01 seconds > > >22 proc sql; >23 create table test as >24 select * from a ,c >25 where a.a=c.a >26 outer union corr >27 select * from b ,c >28 where b.a=c.a; >ERROR: Duplicate column names have been detected in the above query >which requested that > CORRESPONDING column names be matched. This situation is >ambiguous. >29 quit; >NOTE: The SAS System stopped processing this step because of errors. >NOTE: PROCEDURE SQL used: > real time 0.03 seconds > cpu time 0.00 seconds