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CREATE TABLE dbo.GLProject
(project int, amount int, period date);
INSERT dbo.GLProject VALUES
(12345, 10, '20200101'),
(12345, 10, '20200201'),
(12345, 10, '20200301'),
(12345, 10, '20200401'),
(12345, 10, '20200501'),
(12345, 10, '20200601'),
(12345, 24, '20200901')/*,
(23456, 31, '20200101'),
(23456, 55, '20201101')*/;
DECLARE @d date = DATEFROMPARTS(YEAR(getdate()), MONTH(getdate()), 1);
;WITH total_range AS
(
SELECT project, period = MIN(period)
FROM dbo.GLProject
GROUP BY project
UNION ALL
SELECT project, DATEADD(MONTH, 1, period)
FROM total_range
WHERE period < @d
)
SELECT
tr.project,
amount = SUM(COALESCE(p.amount,0)) OVER
(PARTITION BY tr.project ORDER BY tr.period),
period = CONVERT(char(6), tr.period, 112)
FROM total_range AS tr
LEFT OUTER JOIN dbo.GLProject AS p
ON tr.project = p.project
AND tr.period = p.period;
;WITH total_range AS
(
SELECT project, period = MIN(period)
FROM dbo.GLProject
GROUP BY project
UNION ALL
SELECT project, DATEADD(MONTH, 1, period)
FROM total_range
WHERE period < @d
)
SELECT
tr.project,
amount = SUM(COALESCE(p.amount,0)) OVER
(PARTITION BY tr.project ORDER BY tr.period
ROWS UNBOUNDED PRECEDING),
period = CONVERT(char(6), tr.period, 112)
FROM total_range AS tr
LEFT OUTER JOIN dbo.GLProject AS p
ON tr.project = p.project
AND tr.period = p.period;
