[ http://issues.apache.org/jira/browse/DERBY-326?page=comments#action_12378284 ]
Tomohito Nakayama commented on DERBY-326: ----------------------------------------- One more modification between DERBY-326_8.patch and DERBY-326_9.patch ... * Conflict in both of blobclob4BLOB.out was resolved. > Improve streaming of large objects for network server and client > ---------------------------------------------------------------- > > Key: DERBY-326 > URL: http://issues.apache.org/jira/browse/DERBY-326 > Project: Derby > Type: Improvement > Components: Network Client, Performance, Network Server > Reporter: Kathey Marsden > Assignee: Tomohito Nakayama > Attachments: ClobTest.zip, DERBY-326.patch, DERBY-326_2.patch, > DERBY-326_3.patch, DERBY-326_4.patch, DERBY-326_5.patch, > DERBY-326_5_indented.patch, DERBY-326_6.patch, DERBY-326_7.patch, > DERBY-326_8.patch, DERBY-326_9.patch, > ReEncodedInputStream.java.modifiedForLongRun > > Currently the stream writing methods in network server and client require a > length parameter. This means that we have to get the length of the stream > before sending it. For example in network server in EXTDTAInputStream we have > to use getString and getbytes() instead of getCharacterStream and > getBinaryStream so that we can get the length. > SQLAM Level 7 provides for the enhanced LOB processing to allow streaming > without indicating the length, so, the writeScalarStream methods in > network server DDMWriter.java and network client Request.java can be changed > to not require a length. > Code inspection of these methods seems to indicate that while the length is > never written it is used heavily in generating the DSS. One strange thing is > that it appears on error, the stream is padded out to full length with zeros, > but an actual exception is never sent. Basically I think perhaps these > methods need to be rewritten from scratch based on the spec requirements for > lobs. > After the writeScalarStream methods have been changed, then EXTDAInputStream > can be changed to properly stream LOBS. See TODO tags in this file for more > info. I am guessing similar optimizations available in the client as well, > but am not sure where that code is. -- This message is automatically generated by JIRA. - If you think it was sent incorrectly contact one of the administrators: http://issues.apache.org/jira/secure/Administrators.jspa - For more information on JIRA, see: http://www.atlassian.com/software/jira
