Re: Help: Reducing Extents
If you have indexes on these tables you can run:
ALTER index <index-name> to cluster;
on one of the indexes on each of these table. This will effectively
rebuild the tables which is what you want. Be forewarned: you need
enogh space for 2 versions of the table while the command runs.
Of course you could unload the data from the table to disk and then drop
and recreate the table with more appropriate extent sizes.
dbexport/dbimport can also do this for you; if you don't mind rebuilding
the entire database. If you don't specify extent sizes with dbimport
it will allocate squeeze every table into one extent and also give you
a next extent set to 1/10 of the space it needed for the first extent
on each table.
-Bill
}
} I am running a electronic document management system (EDMS) that uses
} Informix 7.22 as a back end to manage the documents. The EDMS system
} warns me when there are database problems that slow performance. In
} this case it warned me that there were too many extends for the tables
} listed below:
}
} DBMS Tables With More Than 5 Extents
} # of Extents Type Name
} 36 Table arrowdev:dm_sysobject_s
} 22 Table arrowdev:syscolumns
} 21 Table arrowdev:dmr_content_s
} 19 Table arrowdev:sysviews
} 17 Table arrowdev:dm_sysobject_r
} 15 Table arrowdev:dmr_content_r
} 14 Table arrowdev:dmi_object
} 12 Table arrowdev:dm_type_r
} 8 Table arrowdev:sysobjstate
} 7 Table arrowdev:dmi_queue_item_s
} 7 Table arrowdev:sysconstraints
} 6 Table sysmaster:syscolumns
}
} How do I reduce the number of extents to improve performance??
}
} Thanks,
} Chad Laity
} chad_laity@arrowintl.com
} wick@fast.net
}
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