Sql 选择通过其值连接的关键点
我有两列，比如键和值。 我需要关于值之间连接的组键，如图所示。相同的值连接关键点。Sql 选择通过其值连接的关键点,sql,mariadb,graph-theory,graph-algorithm,recursive-query,Sql,Mariadb,Graph Theory,Graph Algorithm,Recursive Query,我有两列，比如键和值。 我需要关于值之间连接的组键，如图所示。相同的值连接关键点。 我不知道怎么做。使用10.5.8-MariaDB。这是一个典型的图形漫游问题-需要递归查询，可从MariaDB 10.2.2开始使用 这里有一种方法，首先将边构建为连接节点的元组，然后迭代遍历数据集，跟踪已访问的节点。我们可以通过跟踪访问量最小的节点来识别每个节点所属的组 with recursive edges as ( select t1.lagr_number as lagr_nu
我不知道怎么做。使用10.5.8-MariaDB。这是一个典型的图形漫游问题-需要递归查询，可从MariaDB 10.2.2开始使用 这里有一种方法，首先将边构建为连接节点的元组，然后迭代遍历数据集，跟踪已访问的节点。我们可以通过跟踪访问量最小的节点来识别每个节点所属的组
with recursive
edges as (
select t1.lagr_number as lagr_number1, t2.lagr_number as lagr_number2
from mytable t1
inner join mytable t2 on t2.ltran_number = t1.ltran_number
),
cte as (
select lagr_number1, lagr_number2, concat(lagr_number1, ',', lagr_number2) as visited
from edges
union all
select c.lagr_number1, e.lagr_number2, concat(c.visited, ',', e.lagr_number2)
from cte c
inner join edges e on e.lagr_number1 = c.lagr_number2
where not find_in_set(e.lagr_number2, c.visited)
)
select lagr_number1 as lagr_number, dense_rank() over(order by min(lagr_number2)) as grp
from cte
group by lagr_number1
order by grp, lagr_number1