Question

我有这个大学任务使用来自多个表的SELECT语句创建表，但它不是那么简单......这里的基本信息：

我正在使用2张桌子 -

CITY(city_ID, name);
PERSON(person_ID, name, surname, city_ID); 
--city_ID is FK indicating in which city person was born.

现在我的任务是创建新表

STATISTICS(city_ID, city_name, number_of_births);
--number_of_births is basically a count of people born in each city

问题是我必须只使用SELECT语句才能这样做。

我尝试过这样的事情:(我很清楚这不可行，但是为了让你更好地了解我被困的地方）

CREATE TABLE Statistics AS 
(SELECT city.city_ID, city.name as "city_name", number_of_births AS 
                (SELECT COUNT(*) FROM person WHERE person.city_id = city.city_id)
 FROM city, person);

Answer 1

对于SQL Server，您可以执行SELECT * INTO。像这样：

SELECT
    *
INTO Statistics
FROM (
    SELECT 
        city.city_ID, 
        city.name as "city_name", 
        (SELECT COUNT(*) FROM person WHERE person.city_id = city.city_id) as 'number_of_births'
    FROM city
        inner join person on city.city_id = person.city_id
) t1

Answer 2

（代表问题作者发布）。

好，这真的很混乱。用Oracle方言重写时，Dave Zych的答案是正确的。

CREATE TABLE Statistics AS SELECT * FROM (
    SELECT DISTINCT
        city.city_ID, 
        city.name AS "City_name",
        (SELECT COUNT(*) FROM person WHERE person.city_ID = city.city_ID) AS "number_of_births"
         FROM city  INNER JOIN person ON city.city_ID = person.city_ID);

使用多个表中的select语句创建表

2 个答案: