Table and data are not required to be on all stores. The engine is selected wrt data availability first. Engine is selected on cost basis only if data is available in more than one store.
On Wed, Aug 19, 2015 at 10:03 AM, Wangfei (X) <[email protected]> wrote: > OK, thanks for your reply. > I have another problem, > Lens choose sql engine by cost, so it may send to HIVE or JDBC-compatible > engine uncertainly. > So every engine should have the same table schema and same data, how to > guarantee it? > > > 在 2015/8/19 12:12, amareshwarisr . 写道: > > Yes. It can execute, it will fire it on the engine which accepts the query > - in this case the engine should be able to access the table, then it would > execute. Basically it will do explain of the query on the engine if it > passes it will execute. > > See sample queries here - > https://github.com/apache/incubator-lens/blob/master/lens-examples/src/main/resources/dimension-queries.sql > and > https://github.com/apache/incubator-lens/blob/master/lens-examples/src/main/resources/cube-queries.sql > > Some of the example queries put out there are native queries. > > Thanks > Amareshwari > > On Tue, Aug 18, 2015 at 6:55 PM, Wangfei (X) <[email protected]> wrote: > >> Hello, I want to ask a question about lens. >> Does lens support query like "query execute select id,name from >> dim_table where name != ""first"" " , >> that is , there is no "cube" keyword in the query, whether this query >> will send to HIVE or JDBC-Compatible engine, >> which will not send to OLAP Cube Metastore. I try to find out this >> problem through reading code, but I'm not sure about it. >> > > >
