如何用SQL获取字母数字连续序列范围（中断时自动重置）

需求说明 #

• 从字母数字序列中提取连续范围，序列出现中断时重置范围
• 需区分已占用（已被移除的）和可用范围

测试临时表数据 #

CREATE TABLE #MyTable
    ([Value] varchar(4))

INSERT INTO #MyTable ([Value])
VALUES
    ('AAAA'),
    ('AAAB'),
    ('AAAC'),
    ('AAAD'),
    ('AAAE'),
    ('AAAF'),
    ('AAAG'),
    ('AAAH'),
    ('AAAI'),
    ('AAAJ'),
    ('AAAK'),
    ('AAAL'),
    ('AAAM'),
    ('AAAR'),
    ('AAAS'),
    ('AAAT'),
    ('AAAU'),
    ('AAAV'),
    ('AAAW'),
    ('AAAX'),
    ('AAAY'),
    ('AAAZ'),
    ('AAA0'),
    ('AAA6'),
    ('AAA7'),
    ('AAA8'),
    ('AAA9')

期望输出结果 #

AAAA - AAAM
AAAR - AAA0
AAA6 - AAA9

内容的提问来源于stack exchange，提问作者DSWayne