Sharepoint document library

We have one document library with 20 folders and more than 800 documents. Acco开发者_如何学编程rding to requirement we need to add some extra columns to the existing document library. my Questions are 1) After adding columns what value will gets stored for each document's those columns in doc library. 2) Can I update only those columns for each document in the library.

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1) It depends on what types of column you are using - a bit more info?

2) Create a "flat" view containing your new columns: (Edit the view within the document library, within the "Folders" section of the edit view page you can select "Show all items without folders"). Open the view in data sheet view. You can then bulk edit the columns.