Intercept final result set in Delegate translator.

[rajni.kumari14]

Hi All,

We have a static vdb contains two source model connecting to mysql database and a view model's table 'TEST_PDEN_MEASUREMENT' which is created using 'join' statement.

Following is the transformation query of TEST_PDEN_MEASUREMENT table:

SELECT

  prc.id AS Measure_ID, prc.quantity AS QUANTITY, prc.quantity_type AS QUANTITY_TYPE, prc.quantity_unit AS QUANTITY_UNIT,

  t.converted_value AS TEST_TABLE_CONVERTED_VALUE

    FROM

  SourceOne.perrowconversion AS prc LEFT OUTER JOIN SourceSecond.test AS t ON prc.id = t.id

We have written a delegate translator which intercepts each call that Teiid is executing and its result set.

Now for the transformation query above, Teiid internally change it into two select statement executing in two different thread and gets its results. Then Teiid perform the join operation and returns the result set(final result set).  Delegate intercepts two statement and its result set. We want to intercept the final result set returned by transformed query using delegate translator. Is this possible using delegate? If yes then how can we achieve this?

Thanks,

Rajni

[rareddy]

Rajani,

You can not intercept the final resultset. The first two are the results from the sources where a translator is involved, for the final results there is no involvement of the translator. If you want to intercept that you need to use some kind of SPY driver over the TEIID JDBC Driver.

Ramesh..

[shawkins]

It all comes down to what you are trying to do.  Teiid has support for masking and row based security that may be applicable here.

There is also the path of introducing another vdb that simply points to the existing vdb and uses the Teiid translator - via a delegating translator.  Most constructs (but not all) would be pushed down and you would have a later interception point.

[rajni.kumari14]

Thanks Steven, creating a VDB on top of the existing VDB, worked.I am able to intercept the final resultset using the  delegating translator.