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  1. Teiid
  2. TEIID-1648

Reading CLOB's from Teradata has issues and produces exception when stream is read from a different thread than what the clob was read from the resultset

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    • Icon: Bug Bug
    • Resolution: Won't Do
    • Icon: Critical Critical
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    • 7.4.1
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      The initial problem was seen when running BQT testing against the teradata source. However, when debugging, the exception was occurring on the initial client read of the stream. After reading teradata jdbc driver doc, it talks about how its not thread safe and has issues when different threads are handling blobs/clobs. Which lead me to do a simple client test. 2 tests where run run thru a servlet that obtains the teradata connenction via jndi. Thet are as follows (attached is the sample code after the changes used for #2):

      1. simple execute/select: execute select intkey, objectvalue from bqt1.smalla, for each row, obtain the clob and read the stream (no exception is seen)
      2. execute select and read clob in a different thread: a new thread is created, passing in the clob, thread is started and then proceeds to try to read the stream, exceptions are seen

      I'll attach the sample code.

            rhn-engineering-shawkins Steven Hawkins
            van.halbert Van Halbert (Inactive)
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