SQL Server 2022

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Microsoft SQL Server 2022 (RTM) - 16.0.1000.6 (X64) Oct 8 2022 05:58:25 Copyright (C) 2022 Microsoft Corporation Express Edition (64-bit) on Windows Server 2019 Standard 10.0 <X64> (Build 17763: ) (Hypervisor)

WITH t1 (t1sem, t1ca) as(
	select 202301, 100 union all
	select 202302, 110 union all
	select 202303, 040 union all
	select 202304, 080 union all
	select 202305, 125 union all
	select 202306, 090 union all
	select 202307, 100 union all  
	select 202308, 130 union all
	select 202309, 070 union all
	select 202310, 065 union all
	select 202311, 100 union all  
	select 202312, 110
),
ranges(rng) as (
  SELECT 1 
  UNION ALL
  SELECT rng + 1 FROM ranges
  WHERE rng < 53
)
SELECT t1sem, rng, delta FROM (
	SELECT t1sem, rng, delta, MIN(rng) OVER() AS minrng
	FROM (
		SELECT t1sem, t1ca, rng, sumca, delta, 
			MIN(delta) OVER() AS mindelta
		FROM (
			SELECT t1sem, t1ca, rng, 
				SUM(t1ca) OVER(PARTITION BY rng ORDER BY t1sem ROWS BETWEEN rng PRECEDING AND CURRENT ROW) as sumca,
				ABS(
					SUM(t1ca) OVER(PARTITION BY rng ORDER BY t1sem ROWS BETWEEN rng PRECEDING AND CURRENT ROW) 
					-
					(SELECT SUM(t1ca) / 2.0 FROM t1)
				)
				AS delta
			FROM t1
            CROSS APPLY ranges
		) t1sums
	) mindeltas
	WHERE delta = mindelta 
) minrngs
WHERE minrng = rng
;

Msg 102 Level 15 State 1 Line 28
Incorrect syntax near 'rng'.
Msg 102 Level 15 State 1 Line 33
Incorrect syntax near ')'.