[QODBC-Desktop] Delete Operation Very Slow in DataFlex
Posted by Juliet (QODBC Support) on 03 June 2010 07:31 AM

Troubleshooting: Delete Operation Very Slow in DataFlex

Note: VB Demo is deprecated.

Please refer to How to use the QODBC Test Tool for testing

Problem Description

      I have an 800MB DataFlex table with several million records, and I am trying to delete them all. I need an empty version of the table, and since FlexODBC doesn't support table creation, I am trying to delete the records in a copy of the table. I used the C++ Demo program with the query "DELETE FROM mytablename" which ran for about 15 hours, after which only about 100,000 records had been deleted. Using the VB Demo program and MS Access yielded similar results. The database is on my local machine, a Dual Core machine with 1GB of RAM. Why is this operation so slow, and is there anything I can do to speed it up?


     If I were to delete all the records in a big table in a DataFlex program one by one, it would also take forever. You should use the DataFlex DFFILE utility or the Visual DataFlex Database Builder utility to create new tables.

     Visual DataFlex Personal "Personal" is a unique, no-cost version of Visual DataFlex licensed for private, personal use only. Visual DataFlex Personal helps developers get acquainted with the product without making a financial commitment Provides a free, fast & easy development tool for non-commercial use.

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Visual DataFlex Personal definition

     A fully functional Visual DataFlex Studio license with the exact operating specifications as a commercial license Users must register and provide contact details to get an activation code. The product is delivered in a time-limited form - registration and activation remove the time limit to create a perpetual license Only for private, personal, and non-commercial use. Includes 3-user Client Engine Includes Connectivity Kits for MS-SQL, DB2, Pervasive SQL, and ODBC. Includes Personal Web Application Server Product logo screen displays on each Studio and Client Engine invocation.

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