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Showing posts from 2007

Ingres resource limiting : Part 1(Ingres Query Execution Plan)

There were complaints about having long delays,putting strain on the hardware.(Ingres II 2.6, Unix HP-UX) The problem is that as there are more than 100 users working on the system concurrently, they did not know which report was hogging the system down.Since there are over 10 fully blown application and each one possesses more than 200 (2300 in total) reports it would be really hard identifying the actual SQL queries and optimizing them. As the applications in question range from warehouse monitoring to bookings, the meaning of the 'report' term has a mixed meaning.There are reports that are produced in a weekly,monthly or annual basis and there are frequent printouts during a user's daily work with all sorts of details. An intermediate solution was to capture the QEP for each report as it is generated and check it against some predefined values that set the threshold of the system. If the value generated by the query itself is above the threshold then a warning message

Unix to Windows interoperability by manipulating the printer queue with Perl using the win32 api

The development of 4GL Ingres applications happens on Unix.Access to the Unix environment is made possible through windows terminals using a terminal emulator . When printing a report from inside the 4 GL application , the application calls the 'system' command which passes arguments to the 'report' command.The actual report is run and the output is being redirected to the local printer on windows by sending escape sequences to the terminal emulator which open the local printer port and send the data (pure text) to it in RAW format with no translation whatsoever by the windows driver. The problem is that the report looks not 'pretty' as it consists of dots and dashes acting as placeholders for the textual data. The presentation would be much better in another format like HTML. The plan was to : add HTML tags inside the actual report file,before it is run,so the dot and dashes would be replaced by the tags. In practice each .prln or .pr report co