It reffering to a data connection created and stored in the App
See online Help
I replied on a similar question here: Re: lib in data load editor
Stefan Bäckstrand wrote:
The LIB keyword is to reference to a datasource by name, that has been created by you (or shared to you?), like this:
LIB CONNECT TO 'MyDataSource';
SQL SELECT * FROM `Sales_data`;
The other use of lib is when referring to a library as a folder (or similar), like this:
LOAD * FROM 'lib://PublicData' (html, table is @1);
[..] You could expect that this is something to look out for in the continuation of Qlik Sense later this year, without saying to much.
More information: http://help.qlik.com/sense/en-US/online/index.html#../Subsystems/Qlik_Sense_Desktop_help/Content/LoadData/ConnectToDataSources.htm%3FTocPath%3DWorking%2520with%2520Qlik%2520Sense%7CLoading%2520data%7CUsing%2520the%2520data%2520load%2520editor%7CConnect%2520to%2520data%2520sources%7C_____0
It refers to a Folder Data Connection. So if you in Sense create a Folder Data Connection, you can later reference files in this folder using the name of the connection (in this case 'Executive Dashboard Data'). In this way you isolate direct access to the file system. It may not be that much of interest when running locally in desktop (why bother, when I can just simply use Windows Explorer to access data anyway?), but when deployed on a server, the server admin can define Folder Data Connections, preventing users from gaining direct access to the file-system, but still get hold of data required for building apps.
For more information about lib://, see https://help.qlik.com/sense/en-us/online/index.html#../Subsystems/Qlik_Sense_Desktop_help/Content/LoadData/ConnectToData…