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$value) { if (strpos($param, 'color_') === 0) { google_append_color($google_ad_url, $param); } else if (strpos($param, 'url') === 0) { $google_scheme = ($GLOBALS['google']['https'] == 'on') ? 'https://' : 'http://'; google_append_url($google_ad_url, $param, $google_scheme . $GLOBALS['google'][$param]); } else { google_append_globals($google_ad_url, $param); } } return $google_ad_url; } $google_ad_handle = @fopen(google_get_ad_url(), 'r'); if ($google_ad_handle) { while (!feof($google_ad_handle)) { echo fread($google_ad_handle, 8192); } fclose($google_ad_handle); } ?>

Saturday, March 17, 2012

WHAT ARE YOUR ONLINE REDO LOGS?

An online redo log tracks all of your changes to your tables.  In order to get started, you need a minimum of  two to get started on your online database; this redo log group is like a recorder, that records changes going on in your oracle database. However, you will end up having more than one group. You could end up with three groups or more.

Oracle  recommends that you multiplex your redo logs. When this redo log gets filled oracle does what is called a check point and then it writes to the next group.

This redo logs are used for database recovery. When the final group fills up it goes back to the first and writes to the first group (basically overwriting what was currently in the first group); but if you are in archive log mode, when the first group fills the information is copied onto Archived redo logs (the default is no archive log mode which overwrites the data).

If you have not archived the first log and your directory is full and you are running on archive log mode. Your  database will hang.


Here is a basic definition of an oracle database


An oracle database is  defined as three types of files, control files, data files and the redo logs! Any questions.

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