统计匹配值并以矩阵形式显示

Question

我有以下 tables 和一些示例数据：

Table: TblTestDB

CREATE TABLE TblTestDB (id int,name varchar(100));

INSERT INTO TblTestDB VALUES(1,'Sam'),(2,'Jack'),
                            (3,'Rock'),(4,'Don'),(5,'Tam');

Table: TblDB1

CREATE TABLE TblDB1 (id int,name varchar(100));

INSERT INTO TblDB1 VALUES(1,'Sam'),(2,'Jack'),
                         (3,'Rock');

Table: TblDB2

CREATE TABLE TblDB2 (id int,name varchar(100));

INSERT INTO TblDB2 VALUES(1,'Jazz'),(2,'Dsouze'),
                         (3,'Rock'),(4,'Jack');

Table: TblDB3

CREATE TABLE TblDB3 (id int,name varchar(100));

INSERT INTO TblDB3 VALUES(1,'Sam'),(2,'Jazz'),
                         (3,'Rock');

我想以以下形式显示结果：

TableName   Name    ID
------------------------------
TblDB1      3       3
TblDB2      2       4
TblDB3      2       3

关于结果集的解释：我想显示在 table TblTestDB 和其他（TblDB1,TblDB2,[=19]之间匹配的列值的计数=]).

尝试了以下查询：

查询：

SELECT DB,MAX(Name) AS Name, MAX(ID) AS ID
FROM
(
    SELECT 'TblDB1' AS DB,COUNT(a.Name) AS Name,0 AS ID 
    FROM TblTestDB a
    INNER JOIN TblDB1 b ON a.Name = b.Name
    UNION
    SELECT 'TblDB2' AS DB,COUNT(a.Name) AS Name,0 AS ID 
    FROM TblTestDB a
    INNER JOIN TblDB2 b ON a.Name = b.Name
    UNION
    SELECT 'TblDB3' AS DB,COUNT(a.Name) AS Name,0 AS ID 
    FROM TblTestDB a
    INNER JOIN TblDB3 b ON a.Name = b.Name
    UNION
    SELECT 'TblDB1' AS DB,0 AS Name,COUNT(a.ID) AS ID 
    FROM TblTestDB a
    INNER JOIN TblDB1 b  ON a.ID = b.ID
    UNION
    SELECT 'TblDB2' AS DB,0 AS Name,COUNT(a.ID) AS ID 
    FROM TblTestDB a
    INNER JOIN TblDB2 b  ON a.ID = b.ID
    UNION
    SELECT 'TblDB3' AS DB,0 AS Name,COUNT(a.ID) AS ID 
    FROM TblTestDB a
    INNER JOIN TblDB3 b ON a.ID = b.ID
) a
GROUP BY DB

问题：我可能会显示 10 多个列，如 matrix/pivot，上面的查询根据列列表增长。任何让它简短的更好方法。

Answer 1

SELECT DISTINCT 'TblDB1' AS DB
      ,COUNT(CASE WHEN a.Name = b.Name THEN 1 ELSE NULL END) AS Name
      ,COUNT(CASE WHEN a.ID = b.ID THEN 1 ELSE NULL END) AS ID 
FROM TblTestDB a
CROSS JOIN TblDB1 b
UNION ALL
SELECT DISTINCT 'TblDB2' AS DB
      ,COUNT(CASE WHEN a.Name = b.Name THEN 1 ELSE NULL END) AS Name
      ,COUNT(CASE WHEN a.ID = b.ID THEN 1 ELSE NULL END) AS ID 
FROM TblTestDB a
CROSS JOIN TblDB2 b
UNION ALL
SELECT DISTINCT 'TblDB3' AS DB
      ,COUNT(CASE WHEN a.Name = b.Name THEN 1 ELSE NULL END) AS Name
      ,COUNT(CASE WHEN a.ID = b.ID THEN 1 ELSE NULL END) AS ID 
FROM TblTestDB a
CROSS JOIN TblDB3 b

Answer 2

这个够简单了吧？

SELECT 
    tableName, sum(s.[Name]) as ncnt, max(s.id) as ID
FROM TblTestDB t
cross apply (
    SELECT tableName, count(name) as [name], max(id) as ID
    FROM (
        SELECT 'TblDB1' as tid, * FROM TblDB1
        union
        SELECT 'TblDB2' as tid, * FROM TblDB2
        union
        SELECT 'TblDB3' as tid, * FROM TblDB3
    ) i
    where i.name = t.name
    group by tableName
) s
group by tableName

不确定你的意思，"I may get more than 10 columns to show like matrix/pivot"。例如，如果您要添加一个 Surname 列，它应该单独匹配，还是与 Name 列结合使用？（前者可能有点复杂...）

统计匹配值并以矩阵形式显示

Count the match values and display in matrix form

tsql

sql-server

sql-server-2008-r2