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Questions tagged [isnull]

`ISNULL` is a proprietary SQL function that replaces NULL with the specified replacement value.

ISNULL is a SQL function that replaces NULL with the specified replacement value.

The ANSI/ISO SQL standard function COALESCE serves the same purpose, and is widely implemented.

Reference

MSDN Article

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Finding null value in Dataset - DataRow.IsNull method vs ==DbNull.Value - c#

What are the benefits of using the c# method DataRow.IsNull to determine a null value over checking if the row equals DbNull.value? if(ds.Tables[0].Rows[0].IsNull("ROWNAME")) {do stuff} vs if(ds.Tables[0].Rows[0]["ROWNAME"] == DbNull.value) {do…
Jarrod
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What is the best way to extend null check?

You all do this: public void Proc(object parameter) { if (parameter == null) throw new ArgumentNullException("parameter"); // Main code. } Jon Skeet once mentioned that he sometimes uses the extension to do this check so you can do…
AgentFire
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Computed bit column that returns whether another column is null

I try to have this computed column: CREATE TABLE dbo.Item ( ItemId int NOT NULL IDENTITY (1, 1), SpecialItemId int NULL, --I tried this IsSpecialItem AS ISNULL(SpecialItemId, 0) > 0, --I tried this IsSpecialItem AS…
Shimmy Weitzhandler
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SQL Server Check for IsNull and for Zero

I have the following: set @SomeVariable = @AnotherVariable/isnull(@VariableEqualToZero,1) - 1 If @VariableEqualToZero is null it substitutes the 1. I need it to substitute 1 if @VariableEqualToZero = 0 as well. How do I do this?
Jeff
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Check if variable is_undefined in PHP

In PHP, I want to check if a variable has not been set/defined, where setting a variable NULL is considered set/defined. I'm aware everything here: http://php.net/manual/en/types.comparisons.php including isset(), empty(), and is_null(). None of…
tjbourke
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SQL Server: ISNULL on uniqueidentifier

I am trying to compare a column col1 and a variable @myvar in a WHERE clause. Both usually contain GUIDs, but may also have NULL values. I thought I could get around the fact that NULL=NULL evaluates to FALSE by using WHERE ISNULL(col1,…
TVogt
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Python pandas .isnull() does not work on NaT in object dtype

I have this series: ser=pd.Series([11,22,33,np.nan,np.datetime64('nat')],name='my_series') The series looks like this: 0 11 1 22 2 33 3 NaN 4 NaN Name: my_series, dtype: object But I get only one True for NULL…
ragesz
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Convert native null to string "null"

Is it possible to convert null to string with php? For instance, $string = null; to $string = "null";
Run
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django order by isnull value?

i have a datetime field which can be null and id like to do qs.order_by('field__isnull', 'name') but this results in: Join on field 'field' not permitted. Did you misspell 'isnull' for the lookup type? Is this possible at all?
Andy
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sql server 2008 return value getting shortened when using ISNULL and NULLIF

I have this select statement where I check whether phone number in null or empty and if they are then I would return 'No Phone Number is available'. Like this SELECT Name, ISNULL(NULLIF(Phone, ''), 'No Phone Number is available') AS…
Sidharth
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Entity Framework ISNULL in Where condition

I have a Query in SQL Server : SELECT * FROM MyTable t WHERE ISNULL(t.Status,'') = '' How I can do it in Entity Framework? EDIT: Oh Sorry my code was like WHERE ISNULL(t.Status,'') = ''
Usman Khalid
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mysql if not null, 0 or ""

SELECT * FROM table WHERE id IN ('21') AND (content_id IS NULL OR content_id = 0 OR content_id = '') Is there a shorter way of writing this condition. I have a int() column that could be either: NULL, 0 or EMPTY.
John Magnolia
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How to check if JSON object is empty in Java?

In Java, if I use the following JSON string as an example, how would I check if the objects are empty/null? {"null_object_1" : [], "null_object_2" : [null] } I have tried using: if(!jsonSource.isNull("null_object_1")) {/*null_object_1 is not…
92Jacko
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check if a row value is null in spark dataframe

I am using a custom function in pyspark to check a condition for each row in a spark dataframe and add columns if condition is true. The code is as below: from pyspark.sql.types import * from pyspark.sql.functions import * from pyspark.sql import…
sam
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Stored procedure call with an ISNULL in the assignment. Invalid Syntax?

Above the call to this stored procedure is another call to a different stored procedure. The first procedure will assign something to @NewIdentifier if it needs to, otherwise I need to use the default SaleId. exec myStoredProc @SaleId =…
Brandon
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