We officially started holding hands with our longest trusted allies in 1858, great article from wired.
http://www.wired.co.uk/news/archive/2011-01/18/transatlantic-cables
Monthly Archives: January 2011
SQL Handling Null Values
Having Null Values in your database is a good thing despite those that might tell you otherwsie. Not only does it save space but it is a definitive “im empty” signature. There are of course proper and improper ways to handle SQL Nulls. Just remember never ever try to compare to a null using “=”.
1. A NULL value represents an UNKNOWN value
2. Under ANSI_NULLS ON, two NULL values will never be equal to each other because the two separate values are unknown. With ANSI_NULLS OFF, two separate NULL values will evaluate to equal values.
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IF OBJECT_ID('SalesHistory')>0 DROP TABLE SalesHistory; GO CREATE TABLE [dbo].[SalesHistory] ( [SaleID] [int] IDENTITY(1,1) NOT NULL PRIMARY KEY, [Product] [varchar](10) NULL, [SaleDate] [datetime] NULL, [SalePrice] [money] NULL ) GO DECLARE @i SMALLINT, @Product VARCHAR(10) SET @i = 1 WHILE (@i <=100) BEGIN SET @Product = CASE WHEN @i%2 = 0 THEN 'Computer' ELSE NULL END INSERT INTO SalesHistory(Product, SaleDate, SalePrice) VALUES (@Product, DATEADD(mm, @i, '3/11/1919'), DATEPART(ms, GETDATE()) + (@i + 57)) INSERT INTO SalesHistory(Product, SaleDate, SalePrice) VALUES('BigScreen', DATEADD(mm, @i, '3/11/1927'), DATEPART(ms, GETDATE()) + (@i + 13)) INSERT INTO SalesHistory(Product, SaleDate, SalePrice) VALUES('PoolTable', DATEADD(mm, @i, '3/11/1908'), DATEPART(ms, GETDATE()) + (@i + 29)) SET @i = @i + 1 END GO SELECT * FROM SalesHistory WHERE Product IS NULL /*returns all the null values which is NULL*/ SELECT * FROM SalesHistory WHERE Product = NULL /*returns no rows, since the NULL value cannot be equal to anyother //value.*/ SELECT * FROM SalesHistory WHERE Product IS NOT NULL SELECT ISNULL(Product, 'Missing') FROM SalesHistory /*For every null value in Product it is replaced by ‘Missing’*/ SELECT Product, COUNT(*) AS ProductCount, SUM(SalePrice) AS ProductSales FROM SalesHistory GROUP BY Product |
Any time a NULL value is present in a column that an aggregation is performed on, such as a COUNT, AVG, or SUM function, those values will be ignored and therefore not included in the functions result.
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SELECT COALESCE(Product, ProductDescription, Product, 'Missing Info') FROM SalesHistory |
The COALESCE function returns the first non-NULL value in the field list that it accepts. The COALESCE function is very useful in a join operation or in queries where you are comparing a single value from a list of possible fields to a single value.
How To Restore All Your HTC Widgets
Recently my htc widgets have not been available for my home screen (friend stream, mail music, twitter etc) Im not sure what caused it but none the less its happened.
To get them back is pretty simple.
Note: this will completely reset your home screen layouts and wipe any saved layouts
1. Make sure you have over 15mb free space2. Open Settings
3. Select Applications
4. Select Manage Applications5. Scroll to HTC Sense and select it
6. Hit Clear data
7. Press the home button and wait
8. You will now see your widgets available when trying to add via one of the home screens
Our Global Village
Thought i would link to this
http://www.slideshare.net/AndrePageot/our-global-village-6627341