topic Re: Join Multiple tables from different database in SAS Data Management

Join Multiple tables from different database

Babloo — Sun, 08 Apr 2018 11:20:44 GMT

I'm extracting fields from different databases (DB2, Teradata..)/tables as shown in the image below and now I'm not certain to join all those variables to create a one single SAS dataset. Appreciate if someone of you guide me here.

E.g. Assume I'm extracting field A from table X, field B from table Y and field C from table Z and now I want to create a table XYZ which should have the variables A, B and C

Re: Join Multiple tables from different database

PaigeMiller — Sun, 08 Apr 2018 12:04:43 GMT

proc sql;
    create table xyz as select x.a, y.b, z.c from
         x left join y on  .....  left join z on .....  ;
quit;

Since you didn't specify the joining criteria, I have left those as ......

Re: Join Multiple tables from different database

Babloo — Sun, 08 Apr 2018 12:24:37 GMT

What if I don't have common variables between those tables?

Re: Join Multiple tables from different database

Patrick — Sun, 08 Apr 2018 13:18:26 GMT

@Babloo

You've got the following questions to answer first:

1. What's the logic?

- relationships between the tables

- Join logic

2. Performance

- How can you reduce volumes most efficiently on the data base side before pulling the data into SAS for further processing (joining the tables).

Only when you're really clear about what needs to be done start with implementation using DIS.

Re: Join Multiple tables from different database

Babloo — Sun, 08 Apr 2018 13:39:37 GMT

If there is a relationship between the tables, can I also lookup
transformation instead of Join transformation?

Re: Join Multiple tables from different database

PaigeMiller — Sun, 08 Apr 2018 15:49:00 GMT

@Babloo wrote:
If there is a relationship between the tables, can I also lookup
transformation instead of Join transformation?

These are questions you have to answer, by learning about the databases involved.