Left Join

[#1]

Hello,

I am trying to add 2 tables and map or left join the new fields to my resident table. However, I am finding that even with a left join my volume is increasing by 2.5 times. I was under the assumption a left join would solve this problem. The new tables I am "mapping"  are only description fields. The [enctr id] is my key field. pg. 5 of the attched doc shows the script of my added tables. //***Sec Diag**** and //***Sec Proc***. If someone could make edits and attach a response I would greatly appreciate it.

Thank you,

EK

[rbecher]

Hi EK,

this is hard to solve without any data. It would be better you would upload an example (with example data) as .qvw and the source files.

- Ralf

[danielact]

A left join won't necessarily mean the amount of records stays the same. For example, let's say you have these two tables:

Table1:

Col1     Col2

A          W

B          X

C          Y

D          Z

Table2:

Col1     Col3

A          M

A          N

A          O

B          P

B          Q

B          R

E          S

E          T

E          U

If you load Table1 and do a left join with table2, you'll end up with this:

Col1     Col2     Col3

A          W          M

A          W          N

A          W          O

B          X          P

B          X          Q

B          X          R

C          Y

D          Z

Check in the second table for duplicate values. Using a Load Distinct can help you eliminate those.