[英]Getting the similar column names and count from two tables
我的数据库中有多个表(千个),我想检查一下是否有两个给定的表具有相似的列名。 为此,我创建了3个示例表,如下所示:
table1(song_cast, song_name, song_size)
table2(song_size, singer, movie_name, song_cast)
table3(movie_name, singer, song_name, song_cast)
我期望的输出是
|table1 & table2 | song_cast, song_size | 2 #count of common columns
|table2 & table3 | singer, song_cast, movie_name | 3
|table1 & table3 | song_name, song_cast | 2
我将在java(NetBeans IDE 8.2)中运行此代码,因此将在NetBeans中获得此输出。
使用几个常见的表格表达式,将select ... for xml path ('')
stuff()
与select ... for xml path ('')
字符串连接的select ... for xml path ('')
方法 。
;with cte as (
select c.*
from information_schema.tables t
inner join information_schema.columns c
on t.table_schema = c.table_schema
and t.table_name = c.table_name
where t.table_type='base table'
)
, match as (
select
tables = l.table_name + ' & ' + r.table_name
, l.column_name
from cte l
inner join cte r
on l.column_name = r.column_name
and l.table_name < r.table_name
)
select
tables
, columns = stuff((
select ', '+ column_name
from match i
where m.tables = i.tables
for xml path (''), type).value('(./text())[1]','nvarchar(max)')
,1,2,'')
, matches = count(*)
from match m
group by tables
extrester演示: http ://rextester.com/TLQ28814
收益:
+-----------------+-------------------------------+---------+
| tables | columns | matches |
+-----------------+-------------------------------+---------+
| table1 & table2 | song_cast, song_size | 2 |
| table1 & table3 | song_cast, song_name | 2 |
| table2 & table3 | singer, movie_name, song_cast | 3 |
+-----------------+-------------------------------+---------+
声明:本站的技术帖子网页,遵循CC BY-SA 4.0协议,如果您需要转载,请注明本站网址或者原文地址。任何问题请咨询:yoyou2525@163.com.