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Field format change accidentally to Number and how to add leading 0

By inadvertence one can transform quickly a field containing number in a text format to number format. This mainly happen during the project creation (import) or when creating new column. This conversion to number can lead to a loss of data like leading 0. Here is how to get them back and avoid this to happen again.


Data exploration tutorial with google refine

Recently, Hugh Stimson published a great article: Data Mining My Old Radio Playlists. His post mix tutorials on php scripting, data cleaning with google refine and data analysis with PostgreSQL.

This answer post demonstrate that data analysis is fully doable in google refine using really basic function (I'll be using GREL function only once for the long tail analysis). I guess also this post is a good illustration of my previous post on data exploration using google refine.


Fusion Table, map multiple items with the same location

When you want to map multiple items with the same location in Fusion Table, only one item is displayed and all the others are ignored. There is several workaround to this  major limitation, and the most common is to change slightly your coordinate (longitude / latitude) so your point will appear close to each other on the map (tip from the google fusion team itself). 

When working with large data set, identifying and manually correcting all records sharing the same location can become time consuming. So I've been looking how to deal with this in Google refine and ends up with this straight forward process.