I have a table where, among others, these three columns below are included. These are ID changes saved in the DB, where an ID in this case has gone from 1->2->3->4.
oldID | newID | added
1 | 2 | 2012-11-23
2 | 3 | 2012-11-24
3 | 4 | 2012-11-25
4 | 1 | 2012-11-26
What I would like to do is to send in a oldID parameter and return the newID, stepping through the changes. So for example, if I send in 2 it returns 1.
I'm not getting anything with my SQL-query below because I don't really know what I'm doing.
DECLARE #dateCurrent datetime
DECLARE #datePrevious datetime
DECLARE #oldID int
SET #dateCurrent = '1970-01-01'
SET #datePrevious = '1970-01-01'
SET #oldID = '2'
WHILE (#dateCurrent >= #datePrevious)
BEGIN
SELECT #oldID = newID, #datePrevious = added
FROM theTable
WHERE oldID = #oldID
END
If you want to recurse, you can use common table expressions
eg:
;with cte as
(
select *, 0 as level from yourtable
union all
select t1.old, cte.new, t1.dateadded, level + 1 from yourtable t1
inner join cte on t1.new = cte.old
and t1.dateadded<cte.dateadded
)
select old, new from
(select old, new, ROW_NUMBER() over (partition by old order by level desc) rn from cte)
v
where rn=1
I agree this might not look like the best solution, but I'm not about to change something in a system that has been running since 95'.
I got it to work like this:
DECLARE #dateCurrent datetime
DECLARE #datePrevious datetime
DECLARE #oldID int
SET #dateCurrent = '1970-01-01'
SET #datePrevious = '1970-01-01'
SET #oldID = '2'
WHILE (#datePrevious <= #dateCurrent )
BEGIN
SET #datePrevious = #dateCurrent
SELECT #dateCurrent = t2.added, #oldID = t1.newID
from theTable
inner join theTable t2
on t2.oldID = t1.newID
where t1.oldID = #oldID
END
SELECT #oldID
Related
I am using SQl Server 2014. I have the following T-SQL query (with its corresponding output given below):
USE mydatabase
declare #t table (StayID int)
insert into #t select distinct StayID from DateOfBirth
while ((select count(1) from #t) > 0)
begin
declare #Id int = (select top 1 StayID from #t)
declare #age_tab table (StayID int, Age int, Year1 date)
declare #cage1 smallint = 2, #cage2 smallint = 5
declare #i_a int = (select AdultCount from DateOfBirth where StayID = #Id)
declare #i_c1 int = (select [0-3] from DateOfBirth where StayID = #Id)
declare #i_c2 int = (select [4-6] from DateOfBirth where StayID = #Id)
declare #age int = (select Age from DateOfBirth where StayID = #Id)
declare #Year1 date = (select cast(datepart(year,ArrivalDate) as varchar) from DateOfBirth where StayID = #Id)
while (#i_a>1)
begin
insert into #age_tab select #Id, (#age + 2), #Year1
set #age-=2
set #i_a-=1
end
while (#i_c1>0)
begin
insert into #age_tab select #Id, #cage1, #Year1
set #i_c1-=1
end
while (#i_c2>0)
begin
insert into #age_tab select #Id, #cage2, #Year1
set #i_c2-=1
end
insert into #age_tab select StayID, Age, cast(datepart(year,ArrivalDate) as varchar) from DateOfBirth where StayID = #Id
delete #t where StayID = #Id
end
select * from #age_tab
order by StayID, Age desc
The output of the above query is as follows:
StayID Age Year1
101 54 2016-01-01
101 52 2016-01-01
102 42 2016-01-01
102 40 2016-01-01
102 14 2016-01-01
...
I want to join the output of this query with values from another table in my database. Given the above query uses temporary tables to perform its operation, I am unable to wrap it into a CTE.
The additional information I want to bring to my output is stored in, say, table "t2".
Let's say the output from the query above is temporarily stored in a table called "t1"
So, I want to do something like this:
Select a.*
, b.Cty
from t1 a
LEFT JOIN t2 b on b.StayID = a.StayID
How can I do this?
I have following table:
I want to copy only those records which are from version 0 and their student_id is never repeated in version 1, that means unchanged records. and I want to insert all copied records to same table with version 1. What will be stored procedure for this.
using group by and having max(version) = 0:
insert into student_name (student_id, student_name, version)
select student_id, max(student_name), 1
from student_name
group by student_id
having max(version) = 0
As a stored procedure, taking a parameter for version, that inserts records for students who do not have a record for that version: and outputs the rows that were inserted:
create procedure dbo.insert_new_version (#version int) as
begin;
set nocount, xact_abort on;
insert into student_name (student_id, student_name, version)
output inserted.*
select
student_id
, student_name = max(student_name)
, version = #version
from student_name
group by student_id
having max(version) < #version
end;
rextester demo: http://rextester.com/JSTNI40605
returns:
+-----------+------------+--------------+---------+
| record_id | student_id | student_name | version |
+-----------+------------+--------------+---------+
| 11 | 3 | ccc | 1 |
+-----------+------------+--------------+---------+
You can select the records by doing:
select t.*
from t
where t.version = 0 and
not exists (select 1
from t t2
where t2.student_id = t.student_id and t2.version = 1
);
The rest is just an insert.
I'd suggest using a while loop to go through the table and identify the items that you need to copy, then these values will be
evaluated and if they meet the criterion for re-inserting and then insert them.
Your code should look like the following. Add CREATE PROC part and Edit table names where applicable
(Caveat: I have written this on notepad so if you get a few errors, just try to fix them)
DECLARE #counter int = 0, #row_Count int = 0, #currentId int,
#currentName nvarchar(100), #version int, #current_Student_id int
SET #row_Count = (SELECT COUNT(record_Id) from yourTable)
WHILE #counter <= #row_Count
BEGIN
SET #currentId = (SELECT record_Id FROM (SELECT row_number() over (order by id)
AS RowNum, record_Id FROM yourTable) sub WHERE RowNum=#counter)
SET #currentName = (SELECT student_name FROM yourTable WHERE record_Id = #currentId)
SET #current_Student_id = (SELECT student_id FROM yourTable WHERE record_Id = #currentId)
SET #version = (SELECT version FROM yourTable WHERE record_Id = #currentId)
--USE IF to check if the current version is 0 and the student ID has not been inserted already
IF (SELECT COUNT(record_Id) FROM yourTable WHERE student_id = #current_Student_id AND version = 1) < 1
AND #version = 0
BEGIN
INSERT INTO yourTable (student_id, student_name, version)
VALUES
(
#current_Student_id,
#currentName,
1
)
END
SET #counter = #counter + 1;
END
You can select and insert like this
Insert INTO tableName select t1.student_Id, t1.student_name,1 from tablename t1
where t1.version = 0 and not exists
(select 1 from tablename t2 where t2.student_id = t.student_id and t2.version = 1);
You can try this by LEFT Join:
INSERT INTO tbl
SELECT T1.record_id,T1.student_Id,T1.student_name, 1
FROM tbl T1 LEFT JOIN tbl T2
ON T1.student_Id = T2.student_Id AND T2.version = 1
WHERE T1.version = 0 AND T2.record_id IS NULL
I am completely new to stored procedure. This time, I need to create a stored procedure in MS SQL.
Let's say I have the following table.
Table name: ListOfProducts
--------------------------
SomeID, ProductID
34, 4
35, 8
35, 11
How do I pass in a SomeID. Use this SomeID to select a recordset from table, ListOfProducts. Then loop through this record set.
Let's say I pass in SomeID = 35.
So, the record set will return 2 records with SomeID 35. In the loop, I will get ProductID 8 and 11, which will be used to do another select from another table.
The stored procedure should return the results from the 2nd select.
How can I do this in MS SQL stored procedure?
Sorry, for this newbie question. Thanks for any help.
If you want looping through the records. You can do like:
--Container to Insert Id which are to be iterated
Declare #temp1 Table
(
tempId int
)
--Container to Insert records in the inner select for final output
Declare #FinalTable Table
(
Id int,
ProductId int
)
Insert into #temp1
Select Distinct SomeId From YourTable
-- Keep track of #temp1 record processing
Declare #Id int
While((Select Count(*) From #temp1)>0)
Begin
Set #Id=(Select Top 1 tempId From #temp1)
Insert Into #FinalTable
Select SomeId,ProductId From ListOfProducts Where Id=#Id
Delete #temp1 Where tempId=#Id
End
Select * From #FinalTable
There is probably no point in writing an explicit loop if you don't need to preform some action on the products that can't be done on the whole set. SQL Server can handle stuff like this much better on its own. I don't know what your tables look like, but you should try something that looks more like this.
CREATE PROC dbo.yourProcName
#SomeID int
AS
BEGIN
SELECT
P.ProductId,
P.ProductName
FROM
Product P
JOIN
ListOfProducts LOP
ON LOP.ProductId = P.ProductId
WHERE
LOP.SomeId = #SomeID
END
I had to do something similar in order to extract hours from a select resultset start/end times and then create a new table iterating each hour.
DECLARE #tCalendar TABLE
(
RequestedFor VARCHAR(50),
MeetingType VARCHAR(50),
RoomName VARCHAR(MAX),
StartTime DATETIME,
EndTime DATETIME
)
INSERT INTO #tCalendar(RequestedFor,MeetingType,RoomName,StartTime,EndTime)
SELECT req as requestedfor
,meet as meetingtype
,room as rooms
,start as starttime
,end as endtime
--,u.datetime2 as endtime
FROM mytable
DECLARE #tCalendarHours TABLE
(
RequestedFor VARCHAR(50),
MeetingType VARCHAR(50),
RoomName VARCHAR(50),
Hour INT
)
DECLARE #StartHour INT,#EndHour INT, #StartTime DATETIME, #EndTime DATETIME
WHILE ((SELECT COUNT(*) FROM #tCalendar) > 0)
BEGIN
SET #StartTime = (SELECT TOP 1 StartTime FROM #tCalendar)
SET #EndTime = (SELECT TOP 1 EndTime FROM #tCalendar)
SET #StartHour = (SELECT TOP 1 DATEPART(HOUR,DATEADD(HOUR,0,StartTime)) FROM #tCalendar)
SET #EndHour = (SELECT TOP 1 DATEPART(HOUR,DATEADD(HOUR,0,EndTime)) FROM #tCalendar)
WHILE #StartHour <= #EndHour
BEGIN
INSERT INTO #tCalendarHours
SELECT RequestedFor,MeetingType,RoomName,#StartHour FROM #tCalendar WHERE StartTime = #StartTime AND EndTime = #EndTime
SET #StartHour = #StartHour + 1
END
DELETE #tCalendar WHERE StartTime = #StartTime AND EndTime = #EndTime
END
Do something like this:
Declare #ID int
SET #ID = 35
SELECT
p.SomeID
,p.ProductID
FROM ListOfProducts p
WHERE p.SomeID = #ID
-----------------------
--Or if you have to join to get it
Declare #ID int
SET #ID = 35
SELECT
c.SomeID
,p.ProductID
,p.ProductName
FROM ListOfProducts p
INNER JOIN categories c on p.ProductID = c.SomeID
WHERE p.SomeID = #ID
You can use option with WHILE loop and BREAK/CONTINUE keywords
CREATE PROC dbo.yourProcName
#SomeID int
AS
BEGIN
IF OBJECT_ID('tempdb.dbo.#resultTable') IS NOT NULL DROP TABLE dbo.#resultTable
CREATE TABLE dbo.#resultTable
(Col1 int, Col2 int)
DECLARE #ProductID int = 0
WHILE(1=1)
BEGIN
SELECT #ProductID = MIN(ProductID)
FROM ListOfProducts
WHERE SomeID = #SomeID AND ProductID > #ProductID
IF #ProductID IS NULL
BREAK
ELSE
INSERT dbo.#resultTable
SELECT Col1, Col2
FROM dbo.yourSearchTable
WHERE ProductID = #ProductID
CONTINUE
END
SELECT *
FROM dbo.#resultTable
END
Demo on SQLFiddle
Example:
Suppose the original table contains the following values
AcctNbr StatusDate
------------------
123 01/01/2012
123 01/01/2013
123 12/11/2011
987 01/01/2009
The SQL would create a new table containing
AcctNbr EarliestStatusDate LatestStatusDate
-------------------------------------------
123 12/11/2011 01/01/2013
987 01/01/2009 01/01/2009
I'm looking for an efficient way to do this. I have a method that works, but it takes an unacceptably long time. Does anyone have any optimization tips. Any help would be greatly appreciated.
SET NOCOUNT ON
DROP TABLE loopTemp
DROP TABLE reportTemp
CREATE TABLE loopTemp
( ID int IDENTITY(1, 1) NOT NULL,
AcctNbr varchar(50),
)
CREATE TABLE reportTemp
(
AcctNbr varchar(50),
EarliestStatus Date,
LatestStatus Date
)
INSERT INTO loopTemp
SELECT DISTINCT AcctNbr
FROM AutoStatusHistory
DECLARE #COUNTER AS INT
SET #COUNTER = 1
DECLARE #MAX AS INT
SET #MAX = (SELECT MAX(ID) FROM loopTemp)
WHILE #COUNTER < #MAX BEGIN
DECLARE #ACCOUNT_NUMBER AS varchar(50)
SET #ACCOUNT_NUMBER =
(SELECT AcctNbr FROM loopTemp WHERE ID = #COUNTER)
DECLARE #EARLIESTSTATUSDATE AS DATE
SET #EARLIESTSTATUSDATE = (SELECT MIN(NewStatusDate)
FROM AutoStatusHistory
WHERE AcctNbr = #ACCOUNT_NUMBER)
DECLARE #LATESTSTATUSDATE AS DATE
SET #LATESTSTATUSDATE = (SELECT MAX(NewStatusDate)
FROM AutoStatusHistory
WHERE AcctNbr = #ACCOUNT_NUMBER)
INSERT INTO reportTemp
VALUES (#ACCOUNT_NUMBER, #EARLIESTSTATUSDATE, #LATESTSTATUSDATE)
IF (#COUNTER % 1000) = 0 BEGIN
PRINT #COUNTER
END -- IF
SET #COUNTER = #COUNTER + 1
END -- WHILE
DROP TABLE loopTemp
Unless I'm missing something, this should be extremely simple:
SELECT AcctNbr, MIN(StatusDate) AS EarliestStatusDate,
MAX(StatusDate) AS LatestStatusDate
FROM myTable
GROUP BY AcctNbr
You appear to be using SQL Server. For this, you can do:
select AcctNbr, min(StatusDate) as EarliestStatusDate,
max(StatusDate) as LatestStatusDate
into ReportTemp
from AutoStatusHistory
group by AcctNbr
The into statement saves the results into a table. You might want to use an actual temporary table, with the syntax:
into #ReportTemp
You can use
SELECT *
INTO TableName
FROM (
SELECT AcctNbr, MIN([Status Date]) AS EarliestStatusDate,
MAX([Status Date]) AS LatestStatusDate
FROM myTable
GROUP BY AcctNbr
) RequiredData
I have a column named sequence. The data in this column looks like 1, 2, 3, 4, 5, 7, 9, 10, 15.
I need to find the missing sequence numbers from the table. What SQL query will find the missing sequence numbers from my table? I am expecting results like
Missing numbers
---------------
6
8
11
12
13
14
I am using only one table. I tried the query below, but am not getting the results I want.
select de.sequence + 1 as sequence from dataentry as de
left outer join dataentry as de1 on de.sequence + 1 = de1.sequence
where de1.sequence is null order by sequence asc;
How about something like:
select (select isnull(max(val)+1,1) from mydata where val < md.val) as [from],
md.val - 1 as [to]
from mydata md
where md.val != 1 and not exists (
select 1 from mydata md2 where md2.val = md.val - 1)
giving summarised results:
from to
----------- -----------
6 6
8 8
11 14
I know this is a very old post but I wanted to add this solution that I found HERE so that I can find it easier:
WITH Missing (missnum, maxid)
AS
(
SELECT 1 AS missnum, (select max(id) from #TT)
UNION ALL
SELECT missnum + 1, maxid FROM Missing
WHERE missnum < maxid
)
SELECT missnum
FROM Missing
LEFT OUTER JOIN #TT tt on tt.id = Missing.missnum
WHERE tt.id is NULL
OPTION (MAXRECURSION 0);
Try with this:
declare #min int
declare #max int
select #min = min(seq_field), #max = max(seq_field) from [Table]
create table #tmp (Field_No int)
while #min <= #max
begin
if not exists (select * from [Table] where seq_field = #min)
insert into #tmp (Field_No) values (#min)
set #min = #min + 1
end
select * from #tmp
drop table #tmp
The best solutions are those that use a temporary table with the sequence. Assuming you build such a table, LEFT JOIN with NULL check should do the job:
SELECT #sequence.value
FROM #sequence
LEFT JOIN MyTable ON #sequence.value = MyTable.value
WHERE MyTable.value IS NULL
But if you have to repeat this operation often (and more then for 1 sequence in the database), I would create a "static-data" table and have a script to populate it to the MAX(value) of all the tables you need.
SELECT CASE WHEN MAX(column_name) = COUNT(*)
THEN CAST(NULL AS INTEGER)
-- THEN MAX(column_name) + 1 as other option
WHEN MIN(column_name) > 1
THEN 1
WHEN MAX(column_name) <> COUNT(*)
THEN (SELECT MIN(column_name)+1
FROM table_name
WHERE (column_name+ 1)
NOT IN (SELECT column_name FROM table_name))
ELSE NULL END
FROM table_name;
Here is a script to create a stored procedure that returns missing sequential numbers for a given date range.
CREATE PROCEDURE dbo.ddc_RolledBackOrders
-- Add the parameters for the stored procedure here
#StartDate DATETIME ,
#EndDate DATETIME
AS
BEGIN
SET NOCOUNT ON;
DECLARE #Min BIGINT
DECLARE #Max BIGINT
DECLARE #i BIGINT
IF OBJECT_ID('tempdb..#TempTable') IS NOT NULL
BEGIN
DROP TABLE #TempTable
END
CREATE TABLE #TempTable
(
TempOrderNumber BIGINT
)
SELECT #Min = ( SELECT MIN(ordernumber)
FROM dbo.Orders WITH ( NOLOCK )
WHERE OrderDate BETWEEN #StartDate AND #EndDate)
SELECT #Max = ( SELECT MAX(ordernumber)
FROM dbo.Orders WITH ( NOLOCK )
WHERE OrderDate BETWEEN #StartDate AND #EndDate)
SELECT #i = #Min
WHILE #i <= #Max
BEGIN
INSERT INTO #TempTable
SELECT #i
SELECT #i = #i + 1
END
SELECT TempOrderNumber
FROM #TempTable
LEFT JOIN dbo.orders o WITH ( NOLOCK ) ON tempordernumber = o.OrderNumber
WHERE o.OrderNumber IS NULL
END
GO
Aren't all given solutions way too complex?
wouldn't this be much simpler:
SELECT *
FROM (SELECT row_number() over(order by number) as N from master..spt_values) t
where N not in (select 1 as sequence union
select 2 union
select 3 union
select 4 union
select 5 union
select 7 union
select 10 union
select 15
)
This is my interpretation of this issue, placing the contents in a Table variable that I can easily access in the remainder of my script.
DECLARE #IDS TABLE (row int, ID int)
INSERT INTO #IDS
select ROW_NUMBER() OVER (ORDER BY x.[Referred_ID]), x.[Referred_ID] FROM
(SELECT b.[Referred_ID] + 1 [Referred_ID]
FROM [catalog].[dbo].[Referrals] b) as x
LEFT JOIN [catalog].[dbo].[Referrals] a ON x.[Referred_ID] = a.[Referred_ID]
WHERE a.[Referred_ID] IS NULL
select * from #IDS
Just for fun, I decided to post my solution.
I had an identity column in my table and I wanted to find missing invoice numbers.
I reviewed all the examples I could find but they were not elegant enough.
CREATE VIEW EENSkippedInvoicveNo
AS
SELECT CASE WHEN MSCNT = 1 THEN CAST(MSFIRST AS VARCHAR (8)) ELSE
CAST(MSFIRST AS VARCHAR (8)) + ' - ' + CAST(MSlAST AS VARCHAR (8)) END AS MISSING,
MSCNT, INV_DT FROM (
select invNo+1 as Msfirst, inv_no -1 as Mslast, inv_no - invno -1 as msCnt, dbo.fmtdt(Inv_dt) AS INV_dT
from (select inv_no as invNo, a4glidentity + 1 as a4glid
from oehdrhst_sql where inv_dt > 20140401) as s
inner Join oehdrhst_sql as h
on a4glid = a4glidentity
where inv_no - invno <> 1
) AS SS
DECLARE #MaxID INT = (SELECT MAX(timerecordid) FROM dbo.TimeRecord)
SELECT SeqID AS MissingSeqID
FROM (SELECT ROW_NUMBER() OVER (ORDER BY column_id) SeqID from sys.columns) LkUp
LEFT JOIN dbo.TimeRecord t ON t.timeRecordId = LkUp.SeqID
WHERE t.timeRecordId is null and SeqID < #MaxID
I found this answer here:
http://sql-developers.blogspot.com/2012/10/how-to-find-missing-identitysequence.html
I was looking for a solution and found many answers. This is the one I used and it worked very well. I hope this helps anyone looking for a similar answer.
-- This will return better Results
-- ----------------------------------
;With CTERange
As (
select (select isnull(max(ArchiveID)+1,1) from tblArchives where ArchiveID < md.ArchiveID) as [from],
md.ArchiveID - 1 as [to]
from tblArchives md
where md.ArchiveID != 1 and not exists (
select 1 from tblArchives md2 where md2.ArchiveID = md.ArchiveID - 1)
) SELECT [from], [to], ([to]-[from])+1 [total missing]
From CTERange
ORDER BY ([to]-[from])+1 DESC;
from to total missing
------- ------- --------------
6 6 1
8 8 1
11 14 4
DECLARE #TempSujith TABLE
(MissingId int)
Declare #Id Int
DECLARE #mycur CURSOR
SET #mycur = CURSOR FOR Select Id From tbl_Table
OPEN #mycur
FETCH NEXT FROM #mycur INTO #Id
Declare #index int
Set #index = 1
WHILE ##FETCH_STATUS = 0
BEGIN
if (#index < #Id)
begin
while #index < #Id
begin
insert into #TempSujith values (#index)
set #index = #index + 1
end
end
set #index = #index + 1
FETCH NEXT FROM #mycur INTO #Id
END
Select Id from tbl_Table
select MissingId from #TempSujith
Create a useful Tally table:
-- can go up to 4 million or 2^22
select top 100000 identity(int, 1, 1) Id
into Tally
from master..spt_values
cross join master..spt_values
Index it, or make that single column as PK.
Then use EXCEPT to get your missing number.
select Id from Tally where Id <= (select max(Id) from TestTable)
except
select Id from TestTable
You could also solve using something like a CTE to generate the full sequence:
create table #tmp(sequence int)
insert into #tmp(sequence) values (1)
insert into #tmp(sequence) values (2)
insert into #tmp(sequence) values (3)
insert into #tmp(sequence) values (5)
insert into #tmp(sequence) values (6)
insert into #tmp(sequence) values (8)
insert into #tmp(sequence) values (10)
insert into #tmp(sequence) values (11)
insert into #tmp(sequence) values (14)
DECLARE #max INT
SELECT #max = max(sequence) from #tmp;
with full_sequence
(
Sequence
)
as
(
SELECT 1 Sequence
UNION ALL
SELECT Sequence + 1
FROM full_sequence
WHERE Sequence < #max
)
SELECT
full_sequence.sequence
FROM
full_sequence
LEFT JOIN
#tmp
ON
full_sequence.sequence = #tmp.sequence
WHERE
#tmp.sequence IS NULL
Hmmmm - the formatting is not working on here for some reason? Can anyone see the problem?
i had made a proc so you can send the table name and the key and the result is a list of missing numbers from the given table
SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
create PROCEDURE [dbo].[action_FindMissing_Autoincremnt]
(
#tblname as nvarchar(50),
#tblKey as nvarchar(50)
)
AS
BEGIN
SET NOCOUNT ON;
declare #qry nvarchar(4000)
set #qry = 'declare #min int '
set #qry = #qry + 'declare #max int '
set #qry = #qry +'select #min = min(' + #tblKey + ')'
set #qry = #qry + ', #max = max('+ #tblKey +') '
set #qry = #qry + ' from '+ #tblname
set #qry = #qry + ' create table #tmp (Field_No int)
while #min <= #max
begin
if not exists (select * from '+ #tblname +' where '+ #tblKey +' = #min)
insert into #tmp (Field_No) values (#min)
set #min = #min + 1
end
select * from #tmp order by Field_No
drop table #tmp '
exec sp_executesql #qry
END
GO
SELECT TOP 1 (Id + 1)
FROM CustomerNumberGenerator
WHERE (Id + 1) NOT IN ( SELECT Id FROM CustomerNumberGenerator )
Working on a customer number generator for my company. Not the most efficient but definitely most readable
The table has one Id column.
The table allows for Ids to be inserted at manually by a user off sequence.
The solution solves the case where the user decided to pick a high number