Sql 在动态范围内找到多个最小值和最大值

我得到的结果如图所示

我得到了2个值的范围

1） 从79996到80000

2） 从001001到001003

我想要两个最小值79996和001001，还有两个最大值80000和001003

值或范围不是固定的，可以有多个范围

有可能吗

请帮忙

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此查询将仅选择连续范围的边界（连续整数，在使用此查询之前，应将字符类型列强制转换为整数）：

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范围界限的标准是什么？为什么不建立N个范围，例如79996..79998或001003。。。80000 ?

select distinct tr_no,
case 
when left_ind = 'gap' and right_ind = 'seq' then 'RANGE_MIN'
when left_ind = 'seq' and right_ind = 'gap' then 'RANGE_MAX'
else 'MIN-MAX' end as bound_type
from
(
select job_no, tr_no,
case when abs(tr_no - PREV_TR) = 1 then 'seq' else 'gap' as left_ind,
case when abs(NEXT_TR - tr_no) = 1 then 'seq' else 'gap' as right_ind
from 
(
select job_no, tr_no, 
LEAD(tr_no) over (order by tr_no) as NEXT_TR,
LAG(tr_no) over (order by tr_no) as PREV_TR
from mytable
) m1
) m2
where left_ind = 'gap' or right_ind = 'gap'