Dapper - reader.IsConsumed is false even after reading the last resultset

[minteractive]

I am using Dapper version 1.42.0 and SQL Server as the back end to read multiple result-set by executing a Stored Procedure. The issue is that the IsConsumed property of the reader object is false when the last result-set uses spiltOn option to create multiple objects.

This isn't an issue most of the time as this occurs on the result-set, but in my case I have three result sets in which the last set is optional and the 2nd set uses splitOn option to create multiple objects. I use the reader.IsConsumed to determine whether to Read the last result-set or not and in cases when the stored procedure returns only 2 sets I receive an ObjectDisposed error when the code proceeds to read the 3rd set

[mgravell]

Can I assume this ties into
http://stackoverflow.com/questions/35554284/reader-isconsumed-is-false-but-object-was-disposed/
?

I will try to repro. Do you have a short but complete example I can use to
show the error?
On 23 Feb 2016 4:38 p.m., "minteractive" notifications@github.com wrote:

I am using Dapper version 1.42.0 and SQL Server as the back end to read
multiple result-set by executing a Stored Procedure. The issue is that the
IsConsumed property of the reader object is false when the last result-set
uses spiltOn option to create multiple objects.

This isn't an issue most of the time as this occurs on the result-set, but
in my case I have three result sets in which the last set is optional and
the 2nd set uses splitOn option to create multiple objects. I use the
reader.IsConsumed to determine whether to Read the last result-set or not
and in cases when the store procedure returns only 2 sets I receive an
ObjectDisposed error...

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#469.

[minteractive]

Yes, Below is the sample code I am using to execute the stored procedure,

using (var results = await DbContext.Database.Connection.QueryMultipleAsync("StoredProcedure", parameters, commandType: CommandType.StoredProcedure))
{
    IEnumerable<POCO1> collection1 = await results.ReadAsync<POCO1>();
    IEnumerable<POCO2> collection2 = results.Read<POCO2, Class1, Class2,POCO2>
    (
    (obj, obj1, obj2)
    {
        obj.Prop1 = obj1;
        obj.Prop2 = obj2;
    }, "Col1, Col2");
    //results.IsConsumed is set to false when the procedure returns only two sets.
    if (!results.IsConsumed)
    {
        IEnumerable <POCO3> collection3 = await results.ReadAsync<POCO3>();
    }
}

[mgravell]

Just looking at the code: try adding .ToList() to the end of each of those
calls to Read / ReadAsync. IEnumerable is deferred execution. You need to
consume it now.

Note: for async, the pattern is:

var foo = (await someMethod(...)).ToList()

Meaning: you await before you ToList
On 23 Feb 2016 7:01 pm, "minteractive" notifications@github.com wrote:

Yes, Below is the sample code I am using to execute the stored procedure,

using (var results = await
DbContext.Database.Connection.QueryMultipleAsync("StoredProcedure",
parameters, commandType: CommandType.StoredProcedure))
{
IEnumerable collection1 = await results.ReadAsync();
IEnumerable collection2 = results.Read
(
(obj, obj1, obj2)
{
obj.Prop1 = obj1;
obj.Prop2 = obj2;
}, "Col1, Col2");

//results.IsConsumed is set to false when the procedure returns only two sets.
if(!results.IsConsumed)
{
    IEnumerable<POCO3> collection3 = await results.ReadAsync<POCO3>();
}

}

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#469 (comment)
.

[minteractive]

Thanks, I updated the code and converted that to a list

[mgravell]

And... did that fix it? Or does the problem still occur with the ToList()
in place?
On 23 Feb 2016 8:04 pm, "minteractive" notifications@github.com wrote:

Thanks, I updated the code and converted that to a list

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#469 (comment)
.

[minteractive]

The issue still occurs with ToList()

[mgravell]

OK. I'll have a look and see if I can get a repro from your code
On 23 Feb 2016 9:52 p.m., "minteractive" notifications@github.com wrote:

The issue still occurs with ToList()

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#469 (comment)
.

[mank1504]

Hi all,
I just ran into this issue as well. Here's a sample of the code I'm using:

using (var multi = conn.QueryMultiple(sql, args, transaction)) { while (!multi.IsConsumed) { var keywords = multi.Read<int, CustomObject, CustomObject>((typeID, customObject) => { //Do magic... return customObject; }); } }

In digging through the source I think the issue comes in the SqlMapper.GridReader.cs in the NextResult() function. I'm thinking in the else statement, right after the Dispose() is called, the IsConsumed could be set to true. Or even put the IsConsumed = true in the Dispose() function.

Thoughts?

[NinoFloris]

Another place where IsConsumed is never set, MultiReadInternal<TReturn>(Type[] types, ...
https://github.com/StackExchange/Dapper/blob/master/Dapper/SqlMapper.GridReader.cs#L224