错误1327未声明的变量：学生

Question

CREATE TABLE IT1 ( name VARCHAR(64), roll_no INTEGER )
CREATE TABLE IT2 ( name VARCHAR(64), roll_no INTEGER )
CREATE TABLE IT3 ( name VARCHAR(64), roll_no INTEGER )

INSERT INTO IT1 (name, roll_no) VALUES ('aa','13')
INSERT INTO IT2 (name, roll_no) VALUES ('bb','10')
INSERT INTO IT3 (name, roll_no) VALUES ('cc','78')

SELECT *
INTO Student
FROM ( SELECT 
       IT1.name, IT1.roll_no
       FROM IT1
     UNION 
       SELECT
       IT2.name,IT2.roll_no
       FROM IT2
     UNION
       SELECT 
       IT3.name,IT3.roll_no
       FROM IT3
     ) n
ORDER BY roll_no ASC

Answer 1

MySQL不支持SELECT ... INTO ...语法。

您必须使用INSERT INTO ... SELECT ..语法才能完成此任务。

在此处阅读更多内容.. http://dev.mysql.com/doc/refman/5.0/en/insert-select.html

试试这个

CREATE TABLE IT1 ( name VARCHAR(64), roll_no INTEGER );
CREATE TABLE IT2 ( name VARCHAR(64), roll_no INTEGER );
CREATE TABLE IT3 ( name VARCHAR(64), roll_no INTEGER );

INSERT INTO IT1 (name, roll_no) VALUES ('aa','13');
INSERT INTO IT2 (name, roll_no) VALUES ('bb','10');
INSERT INTO IT3 (name, roll_no) VALUES ('cc','78');

CREATE table student as SELECT *
FROM
  (SELECT IT1.name,
          IT1.roll_no
   FROM IT1
   UNION SELECT IT2.name,
                IT2.roll_no
   FROM IT2
   UNION SELECT IT3.name,
                IT3.roll_no
   FROM IT3) n
ORDER BY roll_no ASC

的 FIDDLE DEMO

Answer 2

首先创建学生表..尝试下面

CREATE table student as SELECT *
FROM
  (SELECT IT1.name,
          IT1.roll_no
   FROM IT1
   UNION SELECT IT2.name,
                IT2.roll_no
   FROM IT2
   UNION SELECT IT3.name,
                IT3.roll_no
   FROM IT3) n
ORDER BY roll_no ASC