my vdb have two model a and b, a is mongdb,b is oracle
i run sql below
select * from a.cd_well where well_id = (select well_id from b.cd_well where well_id='1')
the table a.cd_well have many count data,
why this sql run for a long time，What is the parsing order of the statement
whether first run (select well_id from b.cd_well where well_id='1')
Have you taken a look at the query plan? Here  is the link regarding query plans.
 Query Plans · Teiid Documentation
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