SQL Server: How to achieve re-usability yet flexibility in TSQL - sql

Question

I am using SQL Server 2008 R2. I am having some problems finding an effective coding pattern for SQL which supports code re-usability as well as flexibility. By re-usability, what I mean is keeping SQL queries in Stored Procedures and User Defined Functions.
Now, if I choose Stored Procedures, I will be sacrificing its usability in a query directly. If I choose User Defined Functions, I won't be able to use DML statements.
For example, suppose I created a Stored Procedures which inserts one contact record. Now, if I am having a table which can act as a source of multiple contact records, all I am left with are either WHILE loops or CURSORs, which is clearly not a recommended option, due to its performance drawbacks. And due to the fact that DML statements are not allowed in User Defined Functions, I simply cannot use them for this purpose.
Although, If I am not concerned with code re-usability, then instead of using Stored Procedures I can surely use same set of queries again and again to avoid while loops.
What pattern should I follow?
Here is a similar Stored Procedures:-
ALTER Proc [dbo].[InsertTranslationForCategory]
(
#str nvarchar(max),
#EventId int,
#CategoryName NVarchar(500),
#LanguageId int,
#DBCmdResponseCode Int Output,
#KeyIds nvarchar(max) Output
)as
BEGIN
DECLARE #XmlData XML
DECLARE #SystemCategoryId Int
DECLARE #CategoryId Int
Declare #Counter int=1
Declare #tempCount Int
Declare #IsExists int
Declare #TranslationToUpdate NVarchar(500)
Declare #EventName Varchar(200)
declare #Locale nvarchar(10)
declare #Code nvarchar(50)
declare #KeyName nvarchar(200)
declare #KeyValue nvarchar(500)
select #Locale=locale from languages where languageid = #LanguageId
SET #DBCmdResponseCode = 0
SET #KeyIds = ''
select #EventName = eventName from eventLanguages
where eventID = #EventId
--BEGIN TRY
Select #SystemCategoryId=CategoryId from SystemCategories where Name=rtrim(ltrim(#CategoryName))
Select #CategoryId=CategoryId from Categories where Name=rtrim(ltrim(#CategoryName)) and EventId=#EventId
if (#str='deactivate')
Begin
Delete from Codetranslation where CategoryId=#CategoryId
Update Categories set [Status]=0, Isfilter=0 where CategoryId=#CategoryId and Eventid=#EventId
Set #DBCmdResponseCode=2
return
End
set #XmlData=cast(#str as xml)
DECLARE #temp TABLE
(
Id int IDENTITY(1,1),
Code varchar(100),
Translation varchar(500),
CategoryId int
)
Insert into #temp (Code,Translation,CategoryId)
SELECT
tab.col.value('#Code', 'varchar(200)'),
tab.col.value('#Translation', 'varchar(500)'),#SystemCategoryId
FROM #XmlData.nodes('/Data') AS tab (col)
select #tempCount=Count(*) from #temp
if(IsNull(#CategoryId,0)>0)
Begin
While (#Counter <= #tempCount)
Begin
Select #IsExists= count(sc.categoryid) from #temp t Inner Join SystemCodetranslation sc
On sc.categoryid=t.CategoryId
where ltrim(rtrim(sc.code))=ltrim(rtrim(t.code)) and ltrim(rtrim(sc.ShortTranslation))=ltrim(rtrim(t.Translation))
and t.Id= #Counter
print #IsExists
Select #Code = Code , #KeyValue = Translation from #temp where id=#counter
set #KeyName = ltrim(rtrim(#EventName)) + '_' + ltrim(rtrim(#CategoryName)) + '_' + ltrim(rtrim(#Code)) + '_LT'
exec dbo.AddUpdateKeyValue #EventId,#Locale, #KeyName,#KeyValue,NULL,12
select #KeyIds = #KeyIds + convert(varchar(50),keyvalueId) + ',' from dbo.KeyValues
where eventid = #EventId and keyname = #KeyName and locale = #Locale
set #KeyName = ''
set #KeyValue = ''
Set #Counter= #Counter + 1
Set #IsExists=0
End
End
--- Inser data in Codetranslation table
if(isnull(#CategoryId,0)>0)
Begin
print #CategoryId
Delete from codetranslation where categoryid=#CategoryId
Insert into codetranslation (CategoryId,Code,LanguageId,ShortTranslation,LongTranslation,SortOrder)
SELECT
#CategoryId,
tab.col.value('#Code', 'varchar(200)'), #LanguageId,
tab.col.value('#Translation', 'varchar(500)'),
tab.col.value('#Translation', 'varchar(500)'),0
FROM #XmlData.nodes('/Data') AS tab (col)
Update Categories set [Status]=1 where CategoryId=#CategoryId and Eventid=#EventId
End
Set #DBCmdResponseCode=1
set #KeyIds = left(#KeyIds,len(#KeyIds)-1)
END

Answer 1

You can use table variable parameter for your user defined functions.
following code is an example of using table variable parameter in stored procedure.
CREATE TYPE IdList AS TABLE (Id INT)
CREATE PROCEDURE test
#Ids dbo.IdList READONLY
AS
Select *
From YourTable
Where YourTable.Id in (Select Id From #Ids)
End
GO
In order to execute your stored procedure use following format:
Declare #Ids dbo.IdList
Insert into #Ids(Id) values(1),(2),(3)
Execute dbo.test #Ids
Edit
In order to return Inserted Id, I don't use from Table Variable Parameter. I use following query sample for this purpose.
--CREATE TYPE NameList AS TABLE (Name NVarChar(100))
CREATE PROCEDURE test
#Names dbo.NameList READONLY
AS
Declare #T Table(Id Int)
Insert Into YourTable (Name)
OUTPUT Inserted.Id Into #T
Select Name
From #Names
Select * From #T
End
GO