set ansi_nulls on
set quoted_identifier on
gocreate function [dbo].[ufngetcontactinformation](@contactid int)
returns @retcontactinformation table
(-- columns returned by the function
[contactid] int primary key not null,
[firstname] [nvarchar](50) null,
[lastname] [nvarchar](50) null,
[jobtitle] [nvarchar](50) null,
[contacttype] [nvarchar](50) null
)as
-- returns the first name, last name, job title and contact type for the specified contact.
begin
declare
@firstname [nvarchar](50),
@lastname [nvarchar](50),
@jobtitle [nvarchar](50),
@contacttype [nvarchar](50);
-- get common contact information
select
@contactid = contactid,
@firstname = firstname,
@lastname = lastname
from [person].[contact]
where [contactid] = @contactid;
set @jobtitle =
case
-- check for employee
when exists(select * from [humanresources].[employee] e
where e.[contactid] = @contactid)
then (select [title]
from [humanresources].[employee]
where [contactid] = @contactid)
-- check for vendor
when exists(select * from [purchasing].[vendorcontact] vc
inner join [person].[contacttype] ct
on vc.[contacttypeid] = ct.[contacttypeid]
where vc.[contactid] = @contactid)
then (select ct.[name]
from [purchasing].[vendorcontact] vc
inner join [person].[contacttype] ct
on vc.[contacttypeid] = ct.[contacttypeid]
where vc.[contactid] = @contactid)
-- check for store
when exists(select * from [sales].[storecontact] sc
inner join [person].[contacttype] ct
on sc.[contacttypeid] = ct.[contacttypeid]
where sc.[contactid] = @contactid)
then (select ct.[name]
from [sales].[storecontact] sc
inner join [person].[contacttype] ct
on sc.[contacttypeid] = ct.[contacttypeid]
where [contactid] = @contactid)
else null
end;
set @contacttype =
case
-- check for employee
when exists(select * from [humanresources].[employee] e
where e.[contactid] = @contactid)
then 'employee'
-- check for vendor
when exists(select * from [purchasing].[vendorcontact] vc
inner join [person].[contacttype] ct
on vc.[contacttypeid] = ct.[contacttypeid]
where vc.[contactid] = @contactid)
then 'vendor contact'
-- check for store
when exists(select * from [sales].[storecontact] sc
inner join [person].[contacttype] ct
on sc.[contacttypeid] = ct.[contacttypeid]
where sc.[contactid] = @contactid)
then 'store contact'
-- check for individual consumer
when exists(select * from [sales].[individual] i
where i.[contactid] = @contactid)
then 'consumer'
end;
-- return the information to the caller
if @contactid is not null
begin
insert @retcontactinformation
select @contactid, @firstname, @lastname, @jobtitle, @contacttype;
end;
return;
end;
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