Ramin Hossaini (blog)

Enabling Trace

2010-03-09T13:45:06Z

The TRACE_ENABLED parameter allows you to trace the execution history of Oracle. It should be set to TRUE by default.

The information gathered is stored in the following locations:

#User:
/usr/oracle/admin/sid/udump
#Background:
/usr/oracle/admin/sid/bdump
#Core:
/usr/oracle/admin/sid/cdump

These locations could be different depending on what’s set in your PFILE.

Check if trace is enabled:

SHOW parameter trace_enabled;

Sample output:

SQL> show parameter trace_enabled;
 
NAME                      TYPE      VALUE
------------------------- --------  --------------
trace_enabled             BOOLEAN   TRUE

And if it isn’t enabled, enable it using:

ALTER SYSTEM SET trace_enabled = TRUE;

Note: Prior to version Oracle 9i, this parameter was: _trace_enabled

Starting, stopping, and Status of Oracle Enterprise Manager (EM)

2010-03-08T20:34:51Z

To start the Oracle Enterprise Manager Database Control (from the command-line):

emctl start dbconsole

To get the status:

emctl status dbconsole

To stop the dbconsole

emctl stop dbconsole

To access the EM (with default settings):

http://hostname:5500/em

Update statistics on all objects in a database

2010-02-20T18:12:46Z

This helps Oracle choose the best execution plan for queries:

BEGIN
dbms_stats.gather_database_stats(options=> 'GATHER AUTO');
END;
/

Turning Archive-log mode on and off

2010-02-16T19:10:40Z

You can check what mode the database is in with:

1	SELECT LOG_MODE FROM SYS.V$DATABASE;

If you do not specify an archive-log location, it will end up going to a directory like $ORACLE_HOME/dbs - which can be quite a mess.
Check where it's going:

1	SHOW PARAMETER log_archive_dest;

It would be good practice to set the location if it doesn’t show one.
To turn archive-log-mode on or off:

shutdown database:

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SHUTDOWN IMMEDIATE
STARTUP RESTRICT
SHUTDOWN

Mount the database:

1	ALTER DATABASE MOUNT;

Then issue one of the following:

1 2	ALTER DATABASE NOARCHIVELOG; ALTER DATABASE ARCHIVELOG;

If the location hasn’t been set yet:

1	ALTER SYSTEM SET LOG_ARCHIVE_DEST = "/ARC_LOCATION";

Then open the database:

1	ALTER DATABASE OPEN;

There might also be archivelog related entries in your PFILE, which you should also make changes to.

Listing key Oracle Database files

2010-02-16T18:57:02Z

To get a list of all datafiles, redo-log files and control-files, run the following in SQL*Plus (database must be mounted):

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SELECT MEMBER FROM V$LOGFILE;
SELECT NAME FROM V$DATAFILE;
SELECT VALUE FROM V$PARAMETER WHERE NAME = 'control_files';

An easier way of displaying your control-files is:

1	SHOW PARAMETER control_files;

Stop Wordpress from adding p and br tags

2010-01-09T18:43:04Z

Even without the visual-editor, Wordpress has a habit of adding <p> and <br/> tags

Add this to your templates/pages/whatever and it should take care of the problem.

<?php remove_filter('the_content', 'wpautop'); ?>

Create bevelled text

2009-12-09T16:41:30Z

I might be superfluous in my method here, but it works well for me

Add some text

Added blending-modes:

Final result

Making ‘Fairy Tales’

2009-11-18T21:11:11Z

This time round, I tried to take more screenshots

Getting the different pieces:

I had this from a trip to the Etosha National Park earlier this year:

Plus some stock-photography:

Masking and positioning

There are different ways you can get this step done. You could use the pen-tool too for example. I just chose to brush out parts I didn't need.

Preparing the background

Converted the image to black & white:

Added some clouds - just because I can

And came up with this...

Putting it together

This was the hardest step really. I try to re-draw light in the image and try to draw the attention of the viewer to certain areas of the picture

The mask resulted in some hard-edges, so I gaussian blurred it a little

Added noise:

And gave it a cyan-tint

Some magic

I used a couple of brushes to make this

The final image

And a little bit of tweaking later...

Search through files for a string (Linux)

2009-11-04T16:12:09Z

To search a directory recursively for specific text or a string, use:

find . -exec grep "string to find" '{}' \; -print

Surrealism “Propaganda”

2009-10-30T14:17:05Z

I had this idea for a couple of days and finally decided to do it yesterday. This was the process (very very roughly)

Step 1: Getting the initial photos

This is the embarassing part. You'll look silly almost no matter what - trying to get a self-portrait in a suitable position that you envision. A camera on tripod, remote control and bounce-flash later though (thanks, I like my bedsheets too):

Got some stock-photography from Pierre on DeviantArt

Step 2: Putting the 2 together

I had to give the photo a bit more room at the top, so I photoshopped some more wall there. With composites, sometimes I'll mask out the individual parts as precisely as I can initially and save the respective masks in my channels. In this case, I put them together first and then masked it all together. I think that's a mistake and I should have masked the subject first (me) then masked the television. Could have saved myself quite a bit of time afterwards.

Step 3: Magic

OK, so I skipped a lot of steps - my bad - I didn't take any screenshots. I was too busy wondering "how the hell am I going to get this to blend". I guess there's always a point in these highly-processed photos where I say "I should stop right now, this is just not working", but I keep on going because it's taken so much effort already. Eventually, there's a point where I say "oh, I might have something here". I suppose that makes it all the more rewarding in the end.

I use a lot of different filters and textures and try to burn-and-dodge a lot.

Step 4: Colouring and painting light

I hate masking and I love "painting-light" and manipulating it. I think that if I actually loved masking, I could have some really amazing work.

At this point, I also did a bit of liquifying and stretched/distorted parts of the photo.

Almost 3 hours later, this was the final shot: