Selecting a Data Source 

Logical databases, InfoSets, and table joins are all different techniques for consolidating data from multiple database tables. Logical databases are pre-defined paths for accessing database tables. These paths can be made available to various reports in code form. Logical databases are especially useful if the structure of the data you want to read corresponds to a hierarchical view. This can be realized using a logical database. More information on logical databases can be found under Logical Databases.

InfoSets are used in SAP Query. InfoSets can be based, among others, on logical databases. Since the number of fields in a logical database can be extremely large, you can also hide fields. In addition, you can define help fields that users can edit like database fields. You can attach additional tables to read long texts and store ABAP code, for example.
If you choose an InfoSet as your data source, the InfoSet must come from the standard query area. InfoSets from the global query area may not be used when creating a QuickView (consult the section on Query Areas for more information). Also consult the section Creating and Changing InfoSets found in the SAP Query documentation if you are thinking about using an InfoSet.

Multiple tables can be linked together to form a join. The result set is a table, each of the lines of which contains all the fields of all the tables used in the join. Hierarchical relationships between tables cannot be analyzed using a table join. Table joins must be defined before beginning with QuickView construction. You define joins using a control containing graphical representations of the tables you are joining and of existing relationships between them. Further information is found under Graphical Table Join Definition.