signal on SWiK

Community at work - SIGNAL

Thu, 09 Oct 2008 18:13:26 -0700

Long time ago, I saw a blog post by Jorge Bernal, with a simple implementation of SIGNAL for MySQL stored procedures. If you have ever tried to write MySQL stored procedures, you know how dearly missed is this feature.
I discussed this feature internally, and everyone told me "don't bother, we're going to implement SIGNAL in MySQL 6.1". And indeed, the full implementation for SIGNAL and RESIGNAL is in the roadmap.

What does that mean? Should we wait two or three more years to have a SIGNAL feature? Wouldn't it be nice to have a minimal SIGNAL working today, and get the full thing when it's ready?

A bird in the hand ...

I would like to have SIGNAL available today, and therefore I tested Jorge's patch in the latest 5.1.28 code. It needs some more twisting to get it working. If you want to try it, make sure you have the current patch.
Once you apply the patch and compile the code, you will have a server that accepts a simple "SIGNAL" command, without any parameter.
Here's a simple usage example:
First, you create two stored procedures:


delimiter //

drop procedure if exists less_than_10 //
create procedure less_than_10(i int )
deterministic
begin
    if ( i     then
        set @comment = concat('a valid number was entered (', i,')');
    else
        set @comment = concat('number too high (', i,')') ;
        SIGNAL ;
    end if;
    select concat('everything fine [',@comment,']')  as comment;
end//

drop procedure if exists trapping //
create procedure trapping ()
deterministic
begin
    declare mystatus varchar(20) default 'ok';
    declare continue handler for SQLSTATE '38503'
        set mystatus = 'ERROR';
    call less_than_10(7);
    select mystatus, @comment;
    call less_than_10(17);
    select mystatus, @comment;
    select 'and this is after the error';
end //

delimiter ;

And then we'll try out the simple one, by calling directly the procedure with a SIGNAL.


call less_than_10(2);
+--------------------------------------------------+
| comment                                          |
+--------------------------------------------------+
| everything fine [a valid number was entered (2)] |
+--------------------------------------------------+
1 row in set (0.00 sec)
Query OK, 0 rows affected (0.00 sec)

select @comment;
+--------------------------------+
| @comment                       |
+--------------------------------+
| a valid number was entered (2) |
+--------------------------------+
1 row in set (0.00 sec)

call less_than_10(12);
ERROR 1340 (38503): Exception generated from user-defined function/procedure

select @comment;
+----------------------+
| @comment             |
+----------------------+
| number too high (12) |
+----------------------+
1 row in set (0.00 sec)

next, we call the procedure that traps the exception. This one has full control of the execution flow, with SIGNAL and HANDLER.


call trapping();
+--------------------------------------------------+
| comment                                          |
+--------------------------------------------------+
| everything fine [a valid number was entered (7)] |
+--------------------------------------------------+
1 row in set (0.00 sec)

+----------+--------------------------------+
| mystatus | @comment                       |
+----------+--------------------------------+
| ok       | a valid number was entered (7) |
+----------+--------------------------------+
1 row in set (0.00 sec)

+----------+----------------------+
| mystatus | @comment             |
+----------+----------------------+
| ERROR    | number too high (17) |
+----------+----------------------+
1 row in set (0.00 sec)

+-----------------------------+
| and this is after the error |
+-----------------------------+
| and this is after the error |
+-----------------------------+
1 row in set (0.00 sec)

This less than 30 lines patch is much better than many hacks that we've seen published for years.
What's your take? Would you like to have this feature in MySQL 5.1, while the full thing is being developed for 6.1?

Samsung SWC-E100 ExpressCard and WiMAX is in Baltimore!

Thu, 02 Oct 2008 18:47:17 -0700

Well, the great news is that WiMAX service that I have been complaining about for years is finally here but only still in Baltimore.

We should expect WiMAX to become available in more areas and why is this good?

WiMAX is about 5-10 times faster than Sprint’s CDMA network, meaning this WiMAX broadband card will allow you to surf at Cable DSL speeds anywhere you go.

But until there’s more coverage, you will have to wait.

This WiMAX card is actually cheaper than most broadband cards out on the market today at $59.99 plus there’s no contract, a really good deal if you ask me.

As it’s the first of its kind, the E100 is the only XOHM card we’ve tested so far, so we can’t compare it to other WiMAX equipment. Our overall average speeds were 2.3Mbps down and 915Kbps up, which fits into Sprint’s advertised range of 2-4 megabits down and 500-1500Kbps up. But speeds varied widely depending on signal strength: we achieved downloads as fast as 7.1 megabits, and as slow as 620 kilobits.

via pcworld

Brought to you by: Zedomax.com

Samsung SWC-E100 ExpressCard and WiMAX is in Baltimore!

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Vocoder Has me sounding like a robot

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Robotronic can vocode stereo signals with the internal
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processed with its own with shifted formants!
Each of the audio inputs has a complete channelstrip
with Gate, Compressor and gain stage.
On the outputs you´ve got a 3 Band EQ, Compressor and a
multi effects unit with four lovely signal-pimpers.This unit brings
you the desired vocoding sound which no other software vocoder
is capable of.

Apple’s Compressor & Encore Blu-Ray [via Zemanta]
Homemade Leslie speaker [via Zemanta]

No Tags

Big Fish Audio Presents Analog Attack

Tue, 15 Apr 2008 23:21:53 -0700

Image via Wikipedia

Gear
Analog Attack was developed with analog synth and signal processing gear of today and yesterday The instruments used for this production include: Minimoog, Moog Voyager, Prophet 5, Prophet 600, Andromeda, Se-1x, Omega 8, Arp 2600, Yamaha CS 80, Juno 106, SH 101, Matrix 6.

Key Applications Mixes, Cues, Flash, Podcasts, Online Videos, Websites, GameAudio

Download audio file (anat1.mp3)

take a listen to the demo

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No Tags

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SPro is a free speech signal processing toolkit which provides runtime commands implementing standard feature extraction algorithms for speech related applications and a C library to implement new algorithms and to use SPro files within your own programs.

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signal on SWiK

Community at work - SIGNAL

A bird in the hand ...

Samsung SWC-E100 ExpressCard and WiMAX is in Baltimore!

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