Sql Query return rows,but SqlDataReader return null

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Hello everyone,

I am executing a Sql Server 2008 query which returns a set of rows. When i execute the same query from code, using SqlDataReader ,reader.Read() returns null. Any ideas??

The query is a simple Select Statement,with two declared variables which are used in Where Clause.

Thnx in advance

Posted 4-Sep-13 4:52am

IviKAZAZI

Updated 20-Jul-20 11:47am

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Richard C Bishop 4-Sep-13 10:59am

You need to show your code, we cannot read minds or access your hard drive.

[no name] 4-Sep-13 10:59am

Any ideas? Sure, since the query returns data in SSMS and returns nothing in your code, then you have done something wrong. Any more than that we cannot tell since we cannot remote view your code or read your mind.

IviKAZAZI 4-Sep-13 11:05am

I solved it,the code was ok,i just addad a line of code cmd.ExecuteNonQuery(); before this line rdr = cmd.ExecuteReader(); and it worked. I dont know why this happend but its ok now. Hope this helps anyone else...

2 solutions

Solution 1

Reader.Read does not return null - it can't, the return type is bool which is a value type, and as a result is not nullable.

Probably, what you mean is that it returns no rows, or reader is null and the attempt to use it throws a "null reference" exception.

So, place a breakpoint on the first line of the method, and single step through your code looking at the variables, and what is going on. If you can't work it out fro yourself from that, we would need to see the code that generated the problem, and a better description of exactly what the problem is.

Posted 4-Sep-13 5:06am

OriginalGriff

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IviKAZAZI 9-Sep-13 6:01am

U are right about the NULL, it returned no rows. But i resolved it just by executing the command with ExecuteNonQuery before i executeReader and it worked. Maby the problem is with some decalred sql variables on top of the query.

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IviKAZAZI · Accepted Answer · 2013-09-16T23:02:00

Solution 2

I solved it,the code was ok,i just addad a line of code

C#

cmd.ExecuteNonQuery();

before this line

C#

rdr = cmd.ExecuteReader();

and it worked. I dont know why this happend but its ok now. Hope this helps anyone else...

Posted 16-Sep-13 23:02pm

IviKAZAZI