SQL generationg many sequential random rows

generate-rows.sql

-- Generate 4M rows using Ben-Gan style with 8-row seed
WITH E1(N) AS (
    SELECT 1 UNION ALL SELECT 1 UNION ALL SELECT 1 UNION ALL SELECT 1
    UNION ALL SELECT 1 UNION ALL SELECT 1 UNION ALL SELECT 1 UNION ALL SELECT 1 -- 8-row seed
),
E2(N) AS (SELECT 1 FROM E1 AS a CROSS JOIN E1 AS b), -- 64 rows (8 × 8)
E4(N) AS (SELECT 1 FROM E2 AS a CROSS JOIN E2 AS b), -- 4k rows  (64 × 64)
E8(N) AS (SELECT 1 FROM E4 AS a CROSS JOIN E4 AS b), -- 16M rows  (4k x 4k)
Numbers AS (SELECT TOP (4000000) ROW_NUMBER() OVER (ORDER BY (SELECT NULL)) AS n FROM E8)

SELECT
    'Group ' + CAST((n - 1) / 9 + 1 AS VARCHAR(10)) AS G,
    'Line '  + CAST((n - 1) % 9 + 1 AS VARCHAR(10)) AS Line,
    n AS RowId,
    NEWID() AS GuidCol1,
    NEWID() AS GuidCol2
FROM Numbers