SQL IDENTITIY Column not starting with 1 - sql

Question

I have a temp table in SQL 2014. In this table variable I have an identity column declared.
DECLARE #TempTable TABLE
(
ID int IDENTITY(1,1) PRIMARY KEY
, IncidentResolvedOn date
, IncidentCreatedOn date
, IncidentClosedOn date
, TaskAssigned date
, TaskCompleted date
, TaskID float
, IncidentTeamID int
, TotalDaysOutstanding int
, TierInfo varchar(15)
, Task_NoTask varchar(15)
, Tier_2_Days_Outstanding int
, Tier_1_Days_Outstanding int
, DaysToResolve int
, BadDays int
, StartDate date
, EndDate date
)
When I run the rest of the query the ID column sometimes doesn't start with 1, instead it starts with some random number. The code below is what I use to insert into this table variable.
INSERT INTO #TempTable(IncidentResolvedOn, IncidentCreatedOn, IncidentClosedOn,TaskAssigned, TaskCompleted, TaskID, IncidentTeamID )
SELECT [Incident Resolved On]
, [Incident Created On]
, [Incident Closed On]
, [Task Assigned On]
, [Task Completed On]
, [Task ID]
, IncidentTeamID
FROM HEATData
This happens in both a table variable and temp table. I've never seen this happen before. Usually when I use the IDENTITY(1,1) phrase it always starts with 1 no matter how many times I create that table. Any suggestions out there?

Answer 1

I imagine your connection is staying open and thus, your identity isn't resetting for your local variable. Here's an example.
DECLARE #TempTable TABLE
(
ID int IDENTITY(1,1) PRIMARY KEY,
ID2 int)
insert into #TempTable
values
(1),(2)
select * from #TempTable
delete from #TempTable
insert into #TempTable
values
(1),(2)
select * from #TempTable
Now, if you'd wrap this in it's own batch using GO you could see this wouldn't happen. In fact, you have to re-declare your table variable.
DECLARE #TempTable TABLE
(
ID int IDENTITY(1,1) PRIMARY KEY,
ID2 int)
insert into #TempTable
values
(1),(2)
select * from #TempTable
go
DECLARE #TempTable TABLE
(
ID int IDENTITY(1,1) PRIMARY KEY,
ID2 int)
insert into #TempTable
values
(1),(2)
select * from #TempTable
This would be the same for a #TempTable as well if you didn't explicitly drop the #TempTable or the connection remained open. Of course, for actual tables the increment will continue similarly to the first examaple.