Question

我有多个不同的查询，我想将结果存储到一个表中。此查询的结果可能具有不同的行数和列数。

e.g。我有三个问题：

Q1。 select name,id from employee;（结果有2列2行）

Q2。 select salary from emp_table（结果有1列4行）

Q3。 select country_name,Country_id,count(id) from players group by country_name,Country_id（结果有3列3行）

现在，我想将这些结果存储到一个表中，该表的结构如下：

Query_ID | col1  | col2 | col3
-------------------------------

在此表中，query_id是A1，A2，A3 ......

等查询的唯一ID

当查询结果少于三列时，剩余列应填充为null（对于第一个查询，col3应为null，对于第二个查询，col2和col3应为null）。

期望的输出：

Query_ID | col1   | col2 | col3
----------
A1       | John   | 1356 | NULL
A1       | Mathew | 1667 | NULL
A2       | 1500   | NULL | NULL
A2       | 2000   | NULL | NULL
A2       | 3000   | NULL | NULL
A2       | 3500   | NULL | NULL
A3       | US     | 010  | 25
A3       | UK     | 012  | 26
A3       | GER    | 016  | 16

Answer 1

您可以对字段使用别名，以便为不同的查询设置统一的结果集。

Q1 select name as col1,id as col2, '' as col3 from employee;

对于Q2 select salary as col1, '' as col2, '' as col3 from emp_table

对于Q3 select country_name as col1,Country_id as col2,count(id) as col3 from players group by country_name,Country_id

然后您可以使用insert语句来保存这些查询。例如：

INSERT INTO table (col1,col2,col3) select name as col1,id as col2, '' as col3 from employee;

然后，您可以根据需要使用上述任何查询。

Answer 2

您使用Union All

SELECT  'A1' AS Query_ID, name AS Col1, id AS Col2, '' AS Col3 
FROM employee

UNION ALL

SELECT 'A2' AS Query_ID, salary AS Col1, '' AS Col2, '' AS Col3
FROM emp_table

UNION ALL

SELECT 'A2' AS Query_ID, country_name AS Col1, Country_id AS Col2, count(id) AS Col3
FROM players 
GROUP BY country_name, Country_id

Answer 3

insert into new_table (query_id,col1,col2,col3)
select 'A1' as QUERY_ID,name as col1,id as col2,'' as col3 from employee
union all
select 'A2' AS QUERY_ID,salary as col1,'' as col2,'' as col3 from emp_table
union all
select 'A3' AS QUERY_ID,country_name,Country_id,count(id) from players group by country_name,Country_id;

确保要获取的列的数据类型兼容。假设name列是varchar，你要获取的薪水就是这个失败的数字。

将查询结果存储到一个表中

3 个答案: