INTRODUCTION:
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This is the first public release of my updstats shell scripts
The software is distributed accordingly to the GPL 2.0 license:

http://www.gnu.org/licenses/old-licenses/gpl-2.0.html

DISCLAIMER:
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This software is provided AS IS, without any kind of guarantee. Use at your own risk.
Although the author is an IBM employee, this software was developed outside his job scope. As such
any responsability and credits are due solely to the author.


REQUIREMENTS:
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This software should work in any Unix/Linux version, using KSH or BASH. CSH usage may be possible
but has not been tested


INSTALL:
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Unpack the two scripts (tbl_udpstats and dbs_updstats) into a directory in your PATH


USAGE:
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dbs_updstats will allow you to run statistics for a whole database, a subset of tables and
procedures

tbl_updstats will allow you to run statistics for one specific table.

Both scripts accept -V to show version and -h to show help.
Help should be self explanatory... in any case a few notes:

1- tbl_updstats -l option allows a quick LOW mode to be run. Although LOW suggests it's quick,
in reality it can be the slowest step of update statistics. This is because the system will have to
read all the index pages in an ordered way which causes physical scatered reads.
Option -l will workaround this by running low with a column that does not belong to any index.
This of course will have consequences. Only number of rows and number of pages in systables will be
updated. No index info will be collected.

2- Traditionaly there was a problemwith update statisctis in ANSI databases. Since the updates on
systables is done in a transaction (due to the nature of ANSI databases), some locking errors would
happen. If this is an issue check APAR IC57589:

http://www.ibm.com/support/docview.wss?uid=swg1IC57589



TODO:
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- Create some documentation besides the help included in the scripts
- When we run dbs_updstats it calls tbl_updstats for each table. This then calls dbacces...
For system with many small (or empty) tables like Baan/Infor systems this may have a noticeable
performance impact. Ideally dbs_updstats would prepare all the SQL statements and run all of them
in just dbaccess session.

The author can be reached by email at: domusonline@gmail.com