This can be easily checked in Details pane. You need to select column name for which you want to check Properties of a column → right click → Properties

Yes, it is possible to create a copy of an existing Attribute view. While passing View name and View type, you can select the option of “Copy From” and this will enable Browse option from which you can select any of existing view to copy.

External libraries can be inserted using a file in a normal script tag. SAP UI5 also supports JQuery so it can be done by extending your heading from the controller.var s = document.createElement("script"); s.type = "text/javascript"; s.src = "http://domainname.com/somescript"; $("head").append(s);You can also add any external file using the following command −jQuery.sap.registerModulePath("ModuleName","http://Domainname.com"); jQuery.sap.require("ModuleName.jsFileName");You can navigate to the following path for more details−https://blogs.sap.com/2016/04/22/include-external-javascript-library-in-sapui5/

Note that “sap.ui.model.ClientTreeBinding” which is used by TreeTable in JSONModel or XMLModel supports the parameter arrayNames. You need to pass an array of the model property names to create a sublevel. I would suggest to try below:In XML view:      ... In JSON view:treeTable.bindRows({path: '/pathToData', parameters: { arrayNames: ['children'] }});For more details about SAPui5 tree structure, you can navigate to following link:https://sapui5.netweaver.ondemand.com/sdk/test-resources/sap/ui/table/TreeTable.html?sap-ui-debug=true&sap-ui-language=en-US&sap-ui-theme=sap_bluecrystal&sap-ui-accessibility=true&sap-ui-jqueryversion=1.10.2