topic Re: How to determine if my join is bringing everything ? in Statistical Procedures

How to determine if my join is bringing everything ?

Beto16 — Sun, 29 May 2016 16:59:30 GMT

Hi I have 2 tables that I need to join they don't have like variables ... what I'm using is id and date and time.. here is example

From table A join table B
On B.ID = A.Id
And a.date=b.date and a.time between b.time1 and b.time2
);run:

the data looks like this table A
Id. Date time

A. 05/26/16. 11:53:00
B. 05/29/16. 02:33:00

table B
Id. Date time. Time1. Time2
11
A. 05/26/16. 11:55:00 11:50:00. 12:00:00
B. 05/29/16. 02:35:00. 02:35:00. 02:40:00

What I'm doing is if the time from table A fell within the time range from table B time1 and time 2 ...I'm getting results but not sure if I'm getting everything thanks again for the help

Re: How to determine if my join is bringing everything ?

LinusH — Sun, 29 May 2016 20:21:48 GMT

Your syntax looks OK given that I understood your requirement.
If you want to feel confident with the result, control it.
Start with the result - are the returned records correct?
The look to you source data, pick rows and see if they would match your criteria, and compare with your result.

Re: How to determine if my join is bringing everything ?

Reeza — Sun, 29 May 2016 21:08:32 GMT

You need to develop test cases.

Then check that each case is returning the correct number

of records. Make sure to test edge cases - ones with no

matches either by ID or by time, missing data, and/or a large number of matches.

Also, test each case individually

and then as a set.