Unlock a world of possibilities! Login now and discover the exclusive benefits awaiting you.
I'm new in Qlick.
imagine 2 fact tables one of pharmacy and other of laboratory.If they are concatenated in a one fact table table.
How do I know the patients of drug x who have a laboratory test?.
In SQL this question would be answered with a query between the two tables with a join. The two tables have in common only the patient identifier.
Can I answer if I concatenate the two fact tables? or is necessary that they need to be seperated.
Thanks.
Concatenation will force QlikView to combine the tables, regardless of the structure and content. Equal named columns will be added in each other and unknown columns are simply added.
Your patientid should have the same name and then the data wll be available per patientid.
So, probably, yes.
Hi,
Concatenate is used when you need to merge two or more tables that have identical structures. In the example you have explained, other than patient identifier there is no other columns identical then it is better to keep the tables separate linked to patient identifier.
Check out this document. It will help you understand the differenct between the Join and Concatenate functions. I would like to give credit to the person who created it, but I don't remember where I got it.
Hope it helps!
Malini,
I don't believe your statment is correct. Here is a description of Concatenate from the help text:
A concatenation is in principle the same as the SQL UNION statement, but with two differences: first that Concatenate prefix can be used no matter if the tables have identical field names or not; and secondly that no removal of identical records are made.
Hi,
Though you can force concatenate the tables, I meant to say Concatenate statement could be recommended where you need to merge two or more tables that have identical structures and pertaining to the situation.
Thank you very much.
I expose an example,I think is better to can answer my question.
Suppose a Table of pharmacy
patient id drug date_pharmacy
1 A 20150101
1 B 20150203
2 A 20150210
2 A 20150705
2 C 20150812
3 A 20140312
4 B 20140123
other of laboratory
patient id test_type date_lab
1 3 20150109
1 7 20150206
3 3 20140320
if i concanate.
patient id drug date_pharmacy test_type date_lab
1 A 20150101
1 B 20150203
2 A 20150210
2 A 20150705
2 C 20150812
3 D 20140312
4 B 20140123
1 3 20150109
1 7 20150206
3 3 20140320
Can I answer, with this estructure, the patients of drug A , that they have a test type 3?
I have a lot of Fact tables with similar estructures. Can I have two or more link tables in Qlikview?.
Thank you very much.