SQL Server 2019

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CREATE TABLE dbo.JetSales
(
  ID        int,
  Name      nvarchar(32),
  SalesDate date
);
INSERT dbo.JetSales(ID, Name, SalesDate) VALUES
(1,N'John','20211005'),(1,N'John','20211016'),(1,N'John','20211031'),
(2,N'Mary','20211007'),(2,N'Mary','20211013'),
(3,N'Tank','20211009');

DECLARE @thisMonth date, @firstMonth date;
SET @thisMonth = DATEFROMPARTS(YEAR(getdate()), MONTH(getdate()), 1);
SET @firstMonth = DATEADD(MONTH, -5, @thisMonth);

;WITH m(m) AS 
(
  SELECT @firstMonth
  UNION ALL 
  SELECT DATEADD(MONTH, 1, m) FROM m
  WHERE m < @thisMonth
)
SELECT m FROM m;

DECLARE @sql nvarchar(max) = N'SELECT ID, Name';

;WITH m(m) AS 
(
  SELECT @firstMonth
  UNION ALL 
  SELECT DATEADD(MONTH, 1, m) FROM m
  WHERE m < @thisMonth
)
SELECT @sql += N', 
' + QUOTENAME(CONVERT(char(10), m, 101)) 
  + N' = SUM(CASE WHEN SalesDate >= ' 
  + QUOTENAME(CONVERT(char(8), m, 112), char(39)) + N' 
      AND SalesDate < '
  + QUOTENAME(CONVERT(char(8), DATEADD(MONTH, 1, m), 112), char(39))
  + N' THEN 1 ELSE 0 END)'
FROM m;

SET @sql += N'
FROM dbo.JetSales AS js GROUP BY ID, Name;';

SELECT @sql;
EXEC sys.sp_executesql @sql;

m
2024-03-01
2024-04-01
2024-05-01
2024-06-01
2024-07-01
2024-08-01

(No column name)
SELECT ID, Name, [03/01/2024] = SUM(CASE WHEN SalesDate >= '20240301' AND SalesDate < '20240401' THEN 1 ELSE 0 END), [04/01/2024] = SUM(CASE WHEN SalesDate >= '20240401' AND SalesDate < '20240501' THEN 1 ELSE 0 END), [05/01/2024] = SUM(CASE WHEN SalesDate >= '20240501' AND SalesDate < '20240601' THEN 1 ELSE 0 END), [06/01/2024] = SUM(CASE WHEN SalesDate >= '20240601' AND SalesDate < '20240701' THEN 1 ELSE 0 END), [07/01/2024] = SUM(CASE WHEN SalesDate >= '20240701' AND SalesDate < '20240801' THEN 1 ELSE 0 END), [08/01/2024] = SUM(CASE WHEN SalesDate >= '20240801' AND SalesDate < '20240901' THEN 1 ELSE 0 END) FROM dbo.JetSales AS js GROUP BY ID, Name;

(No column name)

SELECT ID, Name,
[03/01/2024] = SUM(CASE WHEN SalesDate >= '20240301'
AND SalesDate < '20240401' THEN 1 ELSE 0 END),
[04/01/2024] = SUM(CASE WHEN SalesDate >= '20240401'
AND SalesDate < '20240501' THEN 1 ELSE 0 END),
[05/01/2024] = SUM(CASE WHEN SalesDate >= '20240501'
AND SalesDate < '20240601' THEN 1 ELSE 0 END),
[06/01/2024] = SUM(CASE WHEN SalesDate >= '20240601'
AND SalesDate < '20240701' THEN 1 ELSE 0 END),
[07/01/2024] = SUM(CASE WHEN SalesDate >= '20240701'
AND SalesDate < '20240801' THEN 1 ELSE 0 END),
[08/01/2024] = SUM(CASE WHEN SalesDate >= '20240801'
AND SalesDate < '20240901' THEN 1 ELSE 0 END)
FROM dbo.JetSales AS js GROUP BY ID, Name;

ID	Name	03/01/2024	04/01/2024	05/01/2024	06/01/2024	07/01/2024	08/01/2024
1	John	0	0	0	0	0	0
2	Mary	0	0	0	0	0	0
3	Tank	0	0	0	0	0	0