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Drill >> mail # dev >> Drill terminology issue: "schema"


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Re: Drill terminology issue: "schema"
Bob
Thanks for bringing this up.
Below are my thoughts.

In some of the relational databases such as Oracle/SQL server , 'Schema'
and 'Database' actually are different in that a database can have multiple
schemas (each schema is typically associated with a user). This is not
however a common practice across all the relational databases. For example,
in MySQL , schema and database are just same (refer to
http://stackoverflow.com/questions/11618277/difference-between-schema-database-in-mysql
)

Drill has the similar paradigm as MySQL and I believe the behavior above is
expected for 1,2,3 above.  Essentially schemas and databases mean the same
thing.
For the file system based queries, each workspace that the user sets up
corresponds to a schema/database in Drill for the clients to interact with
it (A workspace is conceptually same as a Hive database or a HBase
namespace i.e essentially it is a group of tables).

For 4. above, if I understand the issue correctly, the error message from
the original thread very misleading.
Drill is a distributed query engine on top of databases and adopts a
de-centralized metadata model.Currently Drill allows creating tables/views
within the file system based schemas. Eventually I see this being extended
to Hive and HBase schemas as well.
The error should probably something like this.
 'This schema does not allow creation of new tables/views. Please ensure
that the schema is enabled for write or choose a different schema'.

thanks

On Mon, Aug 11, 2014 at 12:14 PM, Bob Rumsby <[EMAIL PROTECTED]> wrote: