Posted by Marc Fielding on Aug 18, 2010
When creating an index, Oracle versions 10g and above automatically compute optimizer statistics. And even before that, 9i had a COMPUTE STATISTICS clause to accomplish the same thing. Not only does it save the time and effort of running DBMS_STATS, but it also saves the disk I/O involved in such an operation, since all rows are available in the course of index creation.
Now why can’t this happen on a CREATE TABLE AS SELECT command? Most if not all of the statistics gathering steps (high/low value, number of distinct values, and even possibly histograms) can be gathered over the course of a simple table read, which is happening anyway.
Oracle 12.1 maybe?
Posted by Sheeri Cabral on May 4, 2009
Do you have_community_features? I do!
SHOW GLOBAL VARIABLES LIKE 'have_community_features';
+-------------------------+-------+
| Variable_name | Value |
+-------------------------+-------+
| have_community_features | YES |
+-------------------------+-------+
1 row in set (0.00 sec)
I am pretty sure this is one of those variables that MySQL has put in as an unused placeholder, but for now, it is not even documented as unused (as are table_lock_wait_timeout, http://dev.mysql.com/doc/refman/5.1/en/server-system-variables.html, and a Google search restricted to the site dev.mysql.com turns up only one match, which is not useful: http://www.google.com/search?q=site%3Adev.mysql.com+have_community_features
I wonder if Read the rest of this entry . . .
Posted by Jan Polnicky on Jul 23, 2008
I found myself, as a fresh member of The Pythian Group, losing precious moments just to change a few standard administrative settings on my new laptop with Microsoft Windows Vista. Having found the answers, I’m sharing them with you so that you can save some time, or spend it more pleasurably out in the summer.
User Account Control (UAC)
Too many prompts and confirmations for admin tasks? Set “Elevate without prompting” for “User Account Control: Behavior of the elevation prompt for administrators in Admin Approval Mode” under Start -> Settings -> Control Panel -> Administrative Tools -> Local Security Policy -> Security Settings -> Local Policies -> Security Options. Ref: UAC on Wikipedia.
Windows Vista Features
By default, telnet is not installed with Windows Vista. To (re-)enable it, select the Telnet Client check box in Start -> Settings -> Control Panel -> Programs and Features -> “Turn Windows features on or off”. Then, Windows Features dialog -> Telnet Client. Now you may use telnet from the command prompt as you are used to in XP. Ref: FAQ on windowshelp.microsoft.com
Read the rest of this entry . . .
