I'm very new to QlikSense and am trying to do what I think should be a simple operation but am having a few issues...
I have a large JSON blob I am pulling from a REST service that gives me a list of applications and a subsection that provides the associated servers and operating systems. I want to expose this via a Qlik dashboard so users can filter out apps based on various criteria, including the OS type(s). The issue I bump into is how does a user filter out all apps that have a specific OS association, as I cannot filter against null values.
i.e. show all apps where 'IBM' is null should show only #1 & #5
AppId
AppName
IBM
RHEL
Windows
1
Safehaven
-
-
Y
2
RabbitWarren
Y
Y
-
3
Aztec
Y
-
-
4
Walkers
Y
Y
-
5
QuoVardis
-
Y
-
I think the right thing to do is to force an 'N' where I have a null, but I'm not sure what the most efficient approach is to do this (I have a few thousand rows and more OS's than shown ), so any suggestions or examples would be welcome.
Below is a simplified view of the structure and how I create the above.
temp1: generic load AppId, Platform, 'Y' AS PlatformUsed resident TableB;
result: load distinct AppId resident TableA;
FOR i = 0 to NoOfTables() TableList: LOAD TableName($(i)) as Tablename AUTOGENERATE 1 WHERE WildMatch(TableName($(i)), 'temp1.*'); NEXT i
FOR i = 1 to FieldValueCount('Tablename') LET vTable = FieldValue('Tablename', $(i)); LEFT JOIN (result) LOAD * RESIDENT $(vTable); DROP TABLE $(vTable); NEXT i
