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I have to insert 30000 ids in a temporary table ##MyTempTable that has only one column (ID int) and I would like to know which way I could do it fastest.

I have tried 30000 normal inserts 

insert into ##MyTempTable (ID) ...

I have tried 

insert into ##MyTempTable (ID) (
 select 1002000 union all 
 select 1002001 union all 
 select 1002002 ...

The fastest way so far has been:

insert into ##MyTempTable (ID)
values
(1002000),(1002001),(1002002),(1002003) ...

Because this type of insert only accepts a maximum of one thousand rows, so then I repeated that insert 30 times.

Would you be able to help me?

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7
  • What programming language? There is a bulk API, but any advice depends - on the environment. C# has a SqlBulkCopy class for that stuff, for example. – TomTom Jun 10 '13 at 15:34
  • @TomTom - I need to do it in C#. I tried using SqlBulkCopy, and it was much slower. I suppose I didn't use it very well. I tried to create a DataRow for each ID and this loop took ages in comparison to the pure SQL statements. Is there a better way to do this? – Jenninha Jun 10 '13 at 15:37
  • What about not using a data row at all. We do SqlBulkInsert over objects. I reach about 75k inserts per second on lower end hardware. Yes, that is 75000. – TomTom Jun 10 '13 at 15:45
  • @TomTom - would you mind giving me an example of your object that you made the SqlBulkInsert? – Jenninha Jun 10 '13 at 15:48
  • Simple class with properties. The trick is the SqlBulkCopy implementation that uses a special provider. All that is on the internet though and NOT a question to ask here - programming is StackOverflow. Google has details. "SqlBulkCopy with objects" is something you could use. – TomTom Jun 10 '13 at 15:49
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If you are really just trying to insert 30000 ID values that increment by 1, starting at 1002000, I highly doubt you'll be able to rig up anything in C# that will be faster than something like this:

INSERT ##MyTable(ID)
  SELECT 1001999 + n FROM
  (
    SELECT TOP (30000) n = ROW_NUMBER() OVER (ORDER BY s1.[object_id])
    FROM sys.all_objects AS s1
    CROSS JOIN sys.all_objects AS s2
    ORDER BY s1.[object_id]
  ) AS x;

In my lowly Windows VM on a Mac host this occurs sub-second.

For other ideas about generating sets / sequences without looping (e.g. a numbers table may be even faster), see this blog series:

http://www.sqlperformance.com/2013/01/t-sql-queries/generate-a-set-1

http://www.sqlperformance.com/2013/01/t-sql-queries/generate-a-set-2

http://www.sqlperformance.com/2013/01/t-sql-queries/generate-a-set-3

If the values are defined and not some incremental sequence (e.g. 30,000 values you somehow coerced into a DataTable), then you can consider using a table-valued parameter. First, create this type in your database (you just do this once):

CREATE TYPE dbo.MyIDs AS TABLE(ID INT PRIMARY KEY);

Now have a stored procedure that accepts this:

CREATE PROCEDURE dbo.TakeMyIDs
  @m dbo.MyIDs READONLY
AS
BEGIN
  SET NOCOUNT ON;

  INSERT ##MyTable(ID) SELECT ID FROM @m;
END
GO

Now call your stored procedure from C# and pass the DataTable as a parameter:

// assuming an active connection object, conn,
// and a populated DataTable called dtIDs:

SqlCommand cmd = new SqlCommand("dbo.TakeMyIDs", conn);
cmd.CommandType = CommandType.StoredProcedure;
SqlParameter tvp1 = cmd.Parameters.AddWithValue("@m", dtIDs);
tvp1.SqlDbType = SqlDbType.Structured;
cmd.ExecuteNonQuery();
cmd.Dispose();
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  • Hi - no, the ids I have to insert aren't incremented. They are specific ids and can be any ramdom value. The ones I posted there were pure coincidence, because I used a set of examples as test. But they won't be incremented :-( – Jenninha Jun 10 '13 at 15:57
  • @Jenninha then please explain where they're coming from and how your code is currently holding 30,000 values - are they in a DataTable or some other collection? A comma-separated list? A text file? – Aaron Bertrand Jun 10 '13 at 15:59
  • They are ids of a set of search results from a user search that is done outside my application. To be honest I haven't defined how I will receive them yet, so now my test is only by having an array with 30000 ids that I will have to insert in a temporary table in SQL Server. – Jenninha Jun 10 '13 at 16:03
  • Instead of an array put them in a DataTable. If you don't know how to do that then it will be a question more appropriate for StackOverflow I think. Once your values are in a DataTable, this answer should help. – Aaron Bertrand Jun 10 '13 at 16:04
  • I did it, I put it in a DataTable, but it was too slow I believe because of my loop to create the DataRows. I will post my SqlBulkCopy insert in a question on StackOverflow and then everyone can see where I might have done something wrong. Thanks! – Jenninha Jun 10 '13 at 16:12

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