T-SQL Summarize Numbers in One Row - tsql

Question

I need to summarize numbers like
CREATE TABLE #t(num int);
INSERT #t
SELECT 10001 UNION ALL
SELECT 10002 UNION ALL
SELECT 10003 UNION ALL
SELECT 10004 UNION ALL
SELECT 10005 UNION ALL
SELECT 10006 UNION ALL
SELECT 10007 UNION ALL
SELECT 10008 UNION ALL
SELECT 10009 UNION ALL
SELECT 10010 UNION ALL
SELECT 10020 UNION ALL
SELECT 10030 UNION ALL
SELECT 10040 UNION ALL
SELECT 10041 UNION ALL
SELECT 10042 UNION ALL
SELECT 10043 UNION ALL
SELECT 10050 UNION ALL
SELECT 10060 UNION ALL
SELECT 10070 UNION ALL
SELECT 10075 UNION ALL
SELECT 10076 UNION ALL
SELECT 10077;
--DROP TABLE #T;
to a simpler form in such a way that result would be.
10001-10010, 10020, 10030, 10040-10043, 10050, 10060, 10070, 10075-10077
Any help would be highly appreciated.

Answer 1

Try this:
WITH CTE1 AS
(
SELECT *, num - ROW_NUMBER() OVER(ORDER BY num) Corr
FROM #t
), CTE2 AS
(
SELECT MIN(num) MinNum, MAX(num) MaxNum, Corr
FROM CTE1
GROUP BY Corr
)
SELECT CAST(MinNum AS VARCHAR) +
CASE WHEN MaxNum != MinNum THEN ' - ' + CAST(MaxNum AS VARCHAR) ELSE '' END Res
FROM CTE2

Answer 2

DECLARE #Result VARCHAR(MAX);
WITH q AS (
SELECT
Num,
Num - (ROW_NUMBER() OVER (ORDER BY Num)) AS RowNumber
FROM
#t
)
SELECT
#Result = ISNULL(#Result + ',', '') +
CASE WHEN MIN(Num) != MAX(Num)
THEN CAST(MIN(Num) AS VARCHAR) + '-' + CAST(MAX(Num) AS VARCHAR)
ELSE CAST(MIN(Num) AS VARCHAR)
END
FROM q
GROUP BY RowNumber
PRINT #Result
-- Or... SELECT #Result.. whichever.

Answer 3

Try a cursor.
Run your script to create a table, then this
DECLARE cur CURSOR FOR
SELECT num FROM #t
OPEN cur
DECLARE #nm INT;
DECLARE #start INT;
DECLARE #prev INT;
DECLARE #retVal VARCHAR(MAX);
SET #retVal = '';
FETCH NEXT FROM cur INTO #nm
SET #prev = NULL;
SET #start = NULL;
WHILE (##fetch_status = 0)
BEGIN
IF (#prev IS NOT NULL)
BEGIN
IF (#prev = #nm - 1)
BEGIN
SET #prev = #nm;
END
ELSE
BEGIN
IF (#start = #prev)
SET #retVal = #retVal + CAST(#start AS VARCHAR) + ', '
ELSE
SET #retVal = #retVal + CAST(#start AS VARCHAR) + ' - ' + CAST(#prev AS VARCHAR) + ', '
SET #prev = #nm;
SET #start = #nm;
END
END
ELSE
BEGIN
SET #prev = #nm;
SET #start = #nm;
END
--PRINT(#nm)
FETCH NEXT FROM cur INTO #nm
END
CLOSE cur
DEALLOCATE cur
IF (#start = #prev)
SET #retVal = #retVal + CAST(#start AS VARCHAR) + ', '
ELSE
SET #retVal = #retVal + CAST(#start AS VARCHAR) + ' - ' + CAST(#prev AS VARCHAR) + ', '
IF (LEN(#retVal) > 1)
SET #retVal = SUBSTRING(#retVal, 1, LEN(#retVal) - 1)
PRINT(#retVal)