Parameter Sniffing and Reporting service through Visual studio

by Deepak Dhakal 16. June 2009 11:20

Today I had a very bad day. My friend left me a job that he estimated for 2 hours and Now I need to finish that ..There is no chance that i can write multiple pages sql Stored procedures /query and create report in 2 hours ..

It is going to take me at least 15 hours for everything .. Ok that is not the point .. the point .. I spent 5 hours to write all the query .. tested in Sql query manager and ran great ... Thought I was really good .. created a report layout .. added few dataset and ran the report using VS 2005 IDE .. Now the drama begins .. It took 5-10 mins to render report by VS 2005. I went to sql server machine.. checked for task manager .. CPU uses was more than 50% for that 10 mins time .WOW .. When I ran the same query in query manager .. it took less than 5 seconds .. I was upset .. restarted VS .. restarted computer .. nothing happened .. recompiled code .. redeployed .. Nothing ..Nothing at all.. I googled about it .. I am not only one.. If u have same problem ..

Google about "Parameter Sniffing " ..U will see many article about it .. In short the solution was: Suppose I have :

create proc newProc { @name varchar(200) }

as select name from nametable where name=@name

.. go

everytime u call it from outside with even NULL value or some value not equal to varchar(200) SQl server tried to create a brand new execution plan ..

and it takes forever to run the script if u have pretty complex sql..

Sol Very simple .

create proc newProc

{ @name varchar(200) }

@declare @newName varchar(200)

set @newname=@name as

select name from nametable where name=@newname .. go

done !! SQL just ignores to create execution plan and runs the last used plan ..

Ok ..so lesson of today:

There are lot of thing u dont know about .

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So You clicked mouse outside your target .. How to detect it - Flex

by Deepak Dhakal 11. June 2009 09:31

In ActionScript3 event driven programming plays a major part with mouse or key pressed and even a text field having events associated with them. Events indicate action e.g. mouse press corresponds to “mouse down” event and vice versa is “mouse up” event.

To check if mouse release (mouseUp -Event.MOUSE_UP)) has happened on the target object on which mouse down - Event.MOUSE_DOWN took place or a “mouse up outside “event when mouse up has not happened on the target object; there is no predefined event with AS3 unlike its earlier versions that had “onReleaseOutside event”.

To resolve this, we need to add stage event handler for mouse up in mouse down event handler. By adding stage event handler for mouse up will detect any global mouse up event. Hence it will check if the event associates the target object that has mouse down event earlier or it was a mouse up outside event not related with the target object.

Package {
  	 Import flash.display.DisplayObject;
  	 import flash.events.*;

	 public var child: DisplayObject = new DisplayObject ();
	 public function childdown(event:MouseEvent):void
		{
		 // mouse up event happens only when there is mouse down
		 trace("child mouse down");
		 stage.addEventListener(MouseEvent.MOUSE_UP,childUpOutside);
		}

	Public function childUpOutside (event:MouseEvent):void
	{
		 if (event.target != child)
		 {
 			  trace("child mouse up outside");
		 }
	   stage.removeEventListener(MouseEvent.MOUSE_UP, childUpOutside);
	}
}

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Flex

Flex: Mouse Move Event and Slow Rendering

by Deepak Dhakal 4. June 2009 11:12

In flex, if you using Mouse move event to redraw anything .. You might have experienced very slow rendering .

eg:

this.addEventListener(MouseEvent.MOUSE_MOVE, redraw);

and

    public function redraw(anything:Object=null):void{
            //draw something here
                this.graphics.clear();
                this.graphics.lineStyle(3, 0x000000);
                this.graphics.moveTo(startPoint.x, startPoint.y);
                this.graphics.lineTo(endPoint.x, endPoint.y);
                this.scaleTextInput.x = centerPoint.x;
                this.scaleTextInput.y = centerPoint.y;

        }

The Above code results very slow rendering ...

Solution:

Use Event.ENTER_FRAME event instead? Although more resource intensive than the mouse move event, you should receive considerably more updates per second, allowing the mouse to appear more responsive to the user:

Eg:

this.addEventListener(Event.ENTER_FRAME, redraw); instead of

this.addEventListener(MouseEvent.MOUSE_MOVE, redraw);

and You are good to go ..Happy Flexing

82414b76-ce60-4cc3-b32e-278f29d33b4c|2|5.0

Tags: flex rendering

Flex

Flex Tooltip Animation

by Deepak Dhakal 3. June 2009 06:56

So you want to show some animation to show tooltip when U hover over something ? Here is an example that shows a rotating tooltip

Change as you want ..

<?xml version="1.0" encoding="utf-8"?>
<!-- http://blog.flexexamples.com/2007/09/04/adding-animations-and-effects-to-flex-tool-tips/ -->
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml"
        layout="vertical"
        verticalAlign="middle"
        backgroundColor="white"
        creationComplete="init()">

    <mx:Script>
        <![CDATA[
            import mx.managers.ToolTipManager;

            private function init():void {
                ToolTipManager.hideDelay = 2000;
                ToolTipManager.showEffect = rotate;
                ToolTipManager.hideEffect = zoom;
            }
        ]]>
    </mx:Script>

    <mx:Style>
        @font-face {
            src: url("./fonts/arial.ttf");
            fontFamily: "ArialEmbedded";
        }

        ToolTip {
            fontFamily: ArialEmbedded;
        }
    </mx:Style>

    <mx:Rotate id="rotate" />
    <mx:Zoom id="zoom" />

    <mx:Button label="Roll over me to see magic"
            toolTip="Sorry No Magic..." />

</mx:Application>

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Tags: flex animation

Flex

Done Key in iPhone keyBoard

by Deepak Dhakal 30. May 2009 09:01

So You want to add a 'Done' key on iphone , do some specific stuff and make the keywork Invisible .. Then Do the following step.

The Steps below is for when u use Nib file.

1. Open NIb file .. Cliick on view and click on the textbox u want to change the keyboard behavior .

2. Open 'Inspector' from the tool menu and change the return key type to 'done'

3. Go to Connection inspector and change the 'delegate' to file owner of the View Controller ( click on + sign and drag to the File's owner )

4. Create a new method in File owner Controller -(IBAction) pressDoneKey and implement this method and map 'did end on exit' to this new method

- (IBAction)pressDoneKey
{

    [txtClient resignFirstResponder];
    return YES;
}

where txtClient is a textfield ..

like this

#import <UIKit/UIKit.h>

@interface ClientGoViewController : UIViewController {

IBOutlet UITextField *txtClient;

}

@property (nonatomic, retain) IBOutlet UITextField *txtClient;

-(IBAction) pressDoneKey;

@end

and U r good to go

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Tags: iphone keyboard nib done key

iPhone

Sqlite and iPhone

by Deepak Dhakal 29. May 2009 11:05

In celebration of the lifting of the NDA on the iPhone SDK, I decided to write a tutorial on using SQLite on the iPhone.

This tutorial covers the basics of SQLite database creation, things to consider in the design of the database, and some particular things to be aware of when deploying these types of applications to the iPhone.

Once you have finished with these basics, take a look at the SQLiteBooks sample code from the iPhone dev center for details on how to interface with the database from your code.

Step 1: Create a SQLite Database File

There are lots of ways to create a SQLite database file. The easiest way that I have found is to download the SQLite Firefox extension, which provides a GUI to create and manage your SQLite database. The rest of this tutorial will assume you have that extension installed.

In this tutorial we’ll be creating a recipe application, so we are naming our database “recipes”.

To create the database:

Click the “New Database” toolbar button.
Enter the name of the database file.
Click OK.

You will then be prompted for a location to save the database. The ideal place is in the directory of your XCode project.

Step 2: Create the Database Schema

Now we are going to setup our database tables. This will be a very simple database with two tables:

There are entire textbooks about “proper” database design and if you are developing a super large-scale ultra robust data warehouse app, you might want to look them over. However rather than make your eyes glaze over with the merits of third normal form, let me just share a few guidelines that I picked up during several years as a DBA/Database application developer:

Every table should mirror an object, with each non-calculated object property mapping directly to a table field.

In addition to the object properties, every table should have an integer field that is autofilled with a unique identifier (commonly know as the primary key).

Every table that is dependent on a parent table should have a way to refer back to its parent. (This is sometimes called a Foreign Key)

In our application we’re going to have two model objects. A Recipe object, and an Ingredient object. Each recipe object can have 1 or more ingredient child objects. (The blue arrow in the above diagram signifies this, and is called a 1-to many relationship).

The Recipe object has a name and description property. These are both strings, and these map to database fields of type VarChar (meaning Variable length Character string). In addition, the Recipes table has a Recipe_ID field of type Integer. This field is the primary key of the Recipes table.

The ingredient object in our simple application only has one property, Description. Since this is a string it also maps to a VarChar field. Our Ingredients table also has a primary key (Ingredient_ID) which gives us a way to refer to a specific ingredient.

Finally, the Recipe_ID field in the Ingredients table is our foreign key back to the Recipes table. Using that key you can look at any ingredient and know what Recipe it belongs to. More commonly an application will use that key to get all of the ingredients that belong to a specific recipe.

To create the Recipes table, click the “New Table” toolbar button and enter the information as seen below:

Notice that we check the Primary Key and Autoinc checkboxes for the Recipe_ID field. The Primary Key checkbox tells SQLite to treat this field as a Unique Index, meaning that it can guarantee that the values in this field won’t be duplicated and should be kept sorted for faster queries. (Later we’ll talk a little more about optimizing queries by adding additional table indices.)

The Autoinc checkbox tells SQLite how to handle the automatic creation of primary key values. Without autoinc being checked, when a new row is added SQLite sets the primary key to one greater than the current highest primary key. With the box checked, SQLite sets the primary key to one greater than the highest primary key that the table has every had. (Which it keeps track of in its own table called sqlite_sequence). How you set this box will depend on how you want to handle deleted records.

For the Ingredients table, it is much the same:

Notice that we do NOT mark the Recipe_ID field of the Ingredients table as a primary key. It is the primary key of the Recipes table, not of this table. (In this table some people would call the Recipe_ID field the foreign key).

The last thing that we want to do regarding our database schema is to create an index on the Recipe_ID field of the Ingredients table. Since most of our queries that involve this table will involve looking up a specific value in the Recipe_ID field, it will speed things up to have an index on this field. (Note: You really won’t notice a significant speed increase unless your Ingredients table has a lot of records, but since it is a good design principle, we’re going to do it anyway.)

Finally you need to populate the table with some data. You can do that using the SQLite Manager by selecting the table and then clicking the “Add new Record” button, or by selecting the “Execute SQL” tab and using several Insert statements.

For example to insert this data into my Recipes table:

Recipe_ID	Name	Description
1	Omelet	A delicious and eggy breakfast.
2	Grilled Cheese Sandwich	A delicious and cheese filled lunch.
3	Pizza	A classic dinner from the old world.

I could use these three insert statements:

INSERT into Recipes(Name, Description) VALUES(’Omelet’, ‘A delicious and eggy breakfast.’);

INSERT into Recipes(Name, Description) VALUES(’Grilled Cheese Sandwich’, ‘A delicious and cheese filled lunch.’);

INSERT into Recipes(Name, Description) VALUES(’Pizza’, ‘A classic dinner from the old world.’);

Notice that I did not insert the values for the Recipe_ID field. As I mentioned above, since it is the primary key the database calculates those values automatically.

Next comes the Ingredients table:

Ingredient_ID	Recipe_ID	Description
1	1	Eggs
2	1	Water
3	1	Salt
4	2	Bread
5	2	Cheese
6	2	Butter
7	3	Pizza Dough
8	3	Pizza Sauce
9	3	Cheese
10	3	Toppings

Which I could use the following statements for:

INSERT into Ingredients(Recipe_ID, Description) VALUES(1, ‘Eggs’);

INSERT into Ingredients(Recipe_ID, Description) VALUES(1, ‘Water’);

INSERT into Ingredients(Recipe_ID, Description) VALUES(1, ‘Salt’);

INSERT into Ingredients(Recipe_ID, Description) VALUES(2, ‘Bread’);

…

INSERT into Ingredients(Recipe_ID, Description) VALUES(3, ‘Toppings’);

Again notice that I did not specify the values for the table’s primary key (Ingredient_ID), but I did specify the foreign key values (Recipe_ID).

Step 3: Add the Database File to Your XCode Project

To do this, just right click on the Resources folder and select “Add->Existing Files…” and then select the database file that you created.

XCode should automatically add the file that you select to the “Copy Bundle Resources” build phase of your project target. (Meaning that when the program is compiled, your database file is automatically stored in the application bundle’s resource folder so that you can access it from your application.)

Update: Jonathan Wight suggested that instead of embedding the SQLite db file directly into the XCode project, it is better to embed the SQL source file into the project and then setup a compile rule in XCode to generate the db file and embed it into the bundle at compile time. As he points out this has a particular advantage related to source code control. He provides an example of how to do this here.

Step 4: Link to the SQLite Library

Finally you are ready to link to the library that contains all of the SQLite functions. To link to that library, from your XCode project right click the frameworks folder and select “Add->Existing Frameworks…”.

Next, navigate to the your iPhoneSDK folder and select the usr/lib/libsqlite3.0.dylib file. (Don’t be confused by the other libsqlite*.lib files in that folder, they are all just aliases to this one.)

You are now ready to start writing some SQLite code. (Again see the SQLiteBooks sample code for some tips on doing that.)

Update: Jonathan Wight also suggested that it is better to use the other linker flags setting in the the Build tab of the Project settings to link to the SQLite library instead of using the framework method. You can do this by adding the -lsqlite3 flag to that field as shown here:

Project “SQLiteBooks” Info.jpg

This method has the advantage of linking to the correct library no matter what platform you are targeting.

SQLite on the iPhone Nuances

SQLite on the actual iPhone is much slower for some things than on the simulator. In particular the same queries that run in the blink of an eye on the simulator take several seconds to run on the actual device.
If you need to write to your database, make sure you make a copy of it in a location that you can write to. See the SQLiteBooks sample code for an example of how to do this.
Be aware that SQLite extensions such as Full Text Search don’t appear to be compiled into the iPhone SQLite libraries.
Plan for the future! If you plan on adding a feature that relies on a certain table or field in the database make that part of your database design now. This will save you the trouble of having to write all the necessary SQL commands for versioning your database later when you release an application update.

Ref:http://leefalin.com/blog/2008/10/02/iphone-sqlite-database-basics/

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Tags: iphone app store developer

iPhone

<< Previous posts Next posts >>

Deepak Dhakal..Not that personal

Parameter Sniffing and Reporting service through Visual studio

So You clicked mouse outside your target .. How to detect it - Flex

Flex: Mouse Move Event and Slow Rendering

Flex Tooltip Animation

Done Key in iPhone keyBoard