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Create unique constraint on a column which has null values

Posted By:      Posted Date: September 14, 2010    Points: 0   Category :Sql Server
Hi All, I have a table suppose 'Temp' having one of the column as 'ColA' which has some null values as well as non null values. Now i have a requirement to create a unique constraint on it. We have tried but couldnt do it.Apart from having a trigger on insert and update statements is there any other alternate. Can any one please help me on this. Thanks & Regards, Srikanth  

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Null Value/ create new column issue in SQL


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hi  there:

  My source data  is below and it's in CSV format

Days waited


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Explicitly defining Clustered Index and NOT NULL constraint on Primary Key column


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Unique text value in databse column


Hi Everyone!

I know this is probably a very basic question but how do I keep a column's text values unique in SQL server (ie for a unique username)?  The column is not an integer it's varchar(50), and it's not the primary key but I could make it the primary key if recommended.

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Thank you!


How to deal with NULL values in a SQL table


 Hi all

In order to add/update/delete data from a table I build 2 classes: 1 class containing all the table fields and another class with methods to add/insert/update/delete records. I am learning how to avoid errors when your table must use SQL NULL values. One error is when I call my UPDATE method (see below):

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Help: Too many lines of code to achieve a simple goal: keep my NULL SQL values...


Hello all

What is the best way (best practice) to preserve my NULL SQL values in the database
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SSRS Report based on SSAS Cubes doesn't show NULL values correctly

I have a SSRS report which is based on an SSAS Cube. In the Cube the formating of numeric fields that NULL values are properly shown as NULL values. In the Cube Browser and Excel this is shown correctly. However when I design the report already the query against SSAS shows these fields as "0" instead of NULL. Is there a way to fix this or is this a bug ?  
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