Slow stored procedure - sql

Question

I currently have a stored procedure that copies content from one table to another.
However when it is trying to only insert 27 new rows it continues on for over 12 minutes (after which point I stopped it) it said Affected 27 rows 4 times, however changes were not made.
Can you spot any reason the following SP would be slow?
SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
ALTER Procedure [dbo].[sp_CopyCompanyContent]
(
#intCopyFromCompanyID Int,
#intNewCompanyID Int
)
As
Begin
/*
RaisError If any of Odl/New Company ID's are 0
*/
If (#intCopyFromCompanyID = 0 Or #intNewCompanyID = 0)
Begin
RaisError('New Company ID or Old Company ID can not be 0', 16, 1)
Return
End
/*
Create Temp Table For the Content Sections
*/
If Object_ID('tempdb..#ContentSections') IS Not Null
Begin
Drop Table dbo.#ContentSections
End
/*
Have to get all the existing data for the Old company we are copying from.
Have to also add the Max(ContentSectionID) From ContentSection. Max(ContentSectionID) +
The Identity (Added further down due to laziness) will be our seed for the ContentID
*/
Select CS.ContentID,
CS.SectionID,
CS.MenuOrder,
#intNewCompanyID NewCompanyID,
CS.CompanyID OldCompanyID,
CS.SubMenu,
CS.Link,
CS.HeaderMenu,
CS.ParentContentID,
CRS.*
Into dbo.#ContentSections
From dbo.Company COMP
Join dbo.ContentSection CS
On COMP.Company_id = CS.CompanyID
Join dbo.Content CONT
On CONT.ContentID = CS.ContentID
Cross Join (
Select MAx(ContentSectionID) MaxContentSectionID
From dbo.ContentSection CONT
) crs
Where COMP.Company_id = #intCopyFromCompanyID
Order By COMP.Company_id
/*
We now need to create a table for the existing content for the old company.
Also have to create the seed. Same principle as above.
*/
If Object_ID('tempdb..#Content') IS Not Null
Begin
Drop Table dbo.#Content
End
Select CONT.*,
CRS.*
Into dbo.#Content
From dbo.Company COMP
Join dbo.ContentSection CS
On COMP.Company_id = CS.CompanyID
Join dbo.Content CONT
On CONT.ContentID = CS.ContentID
Cross Join (
Select MAx(ContentID) MaxContentID
From dbo.Content CONT
) crs
Where COMP.Company_id = #intCopyFromCompanyID
Order By COMP.Company_id
/*
Add Identity to each of the tables we have created above. The ID fields will add to
the Max of each table to mimic what the future seeds will be.
*/
exec('Alter table #ContentSections Add ID Int Identity(1,1)')
exec('Alter table #Content Add ID Int Identity(1,1)')
/*
Add content data from the temp table.
*/
Insert Into dbo.Content
(
Title,
Content
)
Select Title,
Content
From dbo.#Content
/*
Have to the Content table up to the content sections table
as this contains what ID has been add to the Content Table.
*/
Insert Into dbo.ContentSection
(
ContentID,
SectionID,
MenuOrder,
CompanyID,
SubMenu,
Link,
HeaderMenu,
ParentContentID
)
Select C.MaxContentID + C.ID,
CS.SectionID,
CS.MenuOrder,
CS.NewCompanyID,
CS.Submenu,
CS.Link,
CS.HEaderMEnu,
CS.ParentContentID
From dbo.#Content C
Join dbo.#ContentSections CS
On C.ID = CS.ID
End

Answer 1

First thing to do is check the query plan for the selects since cross joins are dangerous beasts, if i'm not reading it wrong you'd display the same value in CRS.* in every record right?
If so, make that query before the select and stored the result in a variable and display it in the select, something like this.
DECLATE #maxValue INTEGER
Select #maxValue=MAX(ContentID) MaxContentID
From dbo.Content CONT
Select CONT.*,
#maxValue as MaxContentID
Into dbo.#Content
From dbo.Company COMP
Join dbo.ContentSection CS
On COMP.Company_id = CS.CompanyID
Join dbo.Content CONT
On CONT.ContentID = CS.ContentID
Where COMP.Company_id = #intCopyFromCompanyID
Order By COMP.Company_id

Answer 2

It is probably because of the identity (it is 2 times from the 4 times*27 rows)
exec('Alter table #ContentSections Add ID Int Identity(1,1)')
exec('Alter table #Content Add ID Int Identity(1,1)')
Instead, if you don't want to create the table, try to use ROW_NUMBER() OVER()... clause as ID, and then you don't need to create the identity later.
And as I see, you don't even need to use the Temp Tables, because then you can simply use the two select as INSERT INTO .... SELECT ... With the ROW_NUMBER().
It seems you don't make any changes on the Temp Tables, so you probably don't need them. (Only if you want to use them out of the SP's scope)