Re: slow loads
Posted in 1993
}
} I'm having a problem loading 24000 rows of data (at roughly 4k per row).
} I'm using this SQL script to load the data:
}
} load from "./data" insert into testtab;
}
} It loads about 17000 rows in about 1 hour, after that, it slows down to
} about 300 rows/hr.
}
} I'm running Informix Online 4.1.
} When I created the table, I told it to use 110000k for the initial extent.
} There are no indices on the table.
} Disk Mirroring is in effect.
}
} Any ideas on why it is sooooo sloooooww?
A few things. We use dbload to load tables from disk. When you use
dbload, you can set the amount of loads between commits, and never have
to worry about overflowing lock tables or log files. Secondly, when doing
a load, dont apply your indicies until after the load is done. Its much
faster to load into a table without indicies. Third, dont forget to
'update statistics' after a massive load. The query optimizer performs
much better when it knows the correct and current information.
--
Naomi Walker (aka N7FSA) naomi@anasazi.com
If you always agree with your boss, one of you is not necessary.