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Limitations on using DBLink?

e519b78b-1a78-4f36-a57b-bc435d4afca4Feb 25 2015 — edited Feb 25 2015

In a View I have an intensive use of a DBLink

SELECT DISTINCT ...

    FROM

    (

        SELECT v.FIELD1, MAX(v.FIELD2) AS FIELD2

            FROM TABLE2@MYDBLINK vg INNER JOIN TABLE1@MYDBLINK v ON ...

            LEFT OUTER JOIN TABLE1@MYDBLINK v1 ON ...

            WHERE v1.FIELD3 IS NULL AND ...

        GROUP BY v.FIELD3

    ) SEL1

    INNER JOIN TABLE1@MYDBLINK t1 ON ...

    INNER JOIN TABLE2@MYDBLINK t2 ON ...

    INNER JOIN TABLE3@MYDBLINK t3 ON ...

    INNER JOIN TABLE4@MYDBLINK t4 ON ...

    INNER JOIN TABLE5@MYDBLINK t5 ON ...

    INNER JOIN TABLE6@MYDBLINK t6 ON ...

    LEFT OUTER JOIN

    (        SELECT DISTINCT ... FROM TABLE7@MYDBLINK pk INNER JOIN TABLE8@MYDBLINK k ON ... WHERE ...    ) SEL2 ON ...

    LEFT OUTER JOIN TABLE9@MYDBLINK t9 ON ...

    LEFT OUTER JOIN TABLE10 t10 ON ...

    WHERE t10.ID IS NULL

    ORDER BY t5.FIELD1

;

When I first execute a 'SELECT * FROM myView' result show up within seconds. When I execute the same statement again (or even when call the SELECT used in the view) results don't even show up after 20+ Minutes.

When I do the SELECT (without '@MYDBLINK') from the View connected to the User the DBLink MYDBLINK points to I get the results within seconds again.

Can this behaviour be caused by the intense use of a DBLink within one SELECT ?

Kind regards,

Chris

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Locked on Mar 25 2015
Added on Feb 25 2015
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