Both are options (and thats how the bI tools work with Drill today) - Views with explicit Casts - Will return schema definitions as part show schemas/describe table/show columns queries. - Limit 0 queries - This will be good as well if we can modify Caravel to issue such queries (this is what Tableau does)
For now, I think returning metadata to Caravel using the above options will be the solution. The ideal approach would be actually to have a data exploration experience on raw data (without curation) within Caravel itself to create this metadata as needed. -Neeraja On Mon, May 16, 2016 at 2:45 PM, Ted Dunning <ted.dunn...@gmail.com> wrote: > As you suggest, views are a critical way to lock down that kind of > information. > > Select with limit 0 is often used for meta-data exploration. This is more > robust than asking about tables since not everything is necessarily really > in a single table. > > On Mon, May 16, 2016 at 2:12 PM, John Omernik <j...@omernik.com> wrote: > > > Hey all, as part of my exploration of Caravel, I realized knowing the > > types of columns can be valuable... I can say create a view of a > directory > > of parquet allowing the "show tables" to work well, however, the type for > > every column is "ANY" which may work (need to tweak some things) but I am > > guessing may make certain down stream things in Caravel more difficult. > > > > So, just thinking aloud here, would it be possible to "cast" in Views to > > allow the view definition to pass along type information? Even if it > means > > a more verbose view definition, it would be done once, and then down > stream > > tools like Caravel would know the types... > > > > Thoughts? > > > > John > > >
