Re: Quering the Sysmaster Database

Hola, >Some time ago, I saw one or two Select statements on the syssqexplain table >to verify aspects of cost and sorts, scans, indexes and temp files. I >believe the queries are these : > >select [...] from syssqexplain [...] First, let's be sure that we all understand that this table (and many others in the sysmaster db) are not documented, and their use is therefore questionable. Queries like this one may be obviated at any time by changing sysmaster schemas without any notice from Informix. I qoute: "Many other tables in the sysmaster database are part of the system-monitoring interface but are not documented. Their schemas and column content might change from version to version." -Informix-Universal Server Administrator's Guide, Volume 2 Version 9.01 page 38-9, "The System-Monitoring Interface Tables" (and it says the same thing for version 7.2, too) >Every time I execute one of these queries (or any other query on the >sysmaster database) my machine hangs and I have to reboot the server. *Any* other query? The manual also warns of dire (unpredictable) results of certain actions involving the sysmaster database. Let us turn in our hymnal to page 38-6, where it sayeth: "Only user informix can query the SMI tables sysadtinfo and sysaudit." (Though the worst you should get is a permission error.) >If anyone knows what this can be I'd like to know. I already contacted the >Tech Support and they don't know why is this occuring. I do not know why this would occur, but if I were you I would do several things before calling Informix support or writing c.d.i.: 1) Ensure that the test query is run properly as user informix, against documented, supported sysmaster tables. 2) Use a very simple query that is immediately easy to understand. 3) provide all the info you could about the nature of the "hang." (The entire machine locks up and will not respond to anything but a manual reboot? Or just the OnLine server?) Your goal here is to differentiate yourself from the vast majority of users with a problem who have simply not RTFM. Do this by addressing the potential causes of your problem as identified there. Then your purpose is to provide your helpful audience with the information they need to solve your problem--not too much data--(that will just get deleted) but just the right amount. Try to present an interesting challenge to the many nerds in the world with nothing better to do than searching for the answers to someone else's problem on c.d.i. ;) After all that, good luck. ______________________________________________________ Clem Akins (aka clema@informix.com) Informix Software, Inc (Standard disclaimers apply) International Technical Support Last seen: Strolling across moonlit Tiananmen Square