Using CREATE TABLE AS statement with UNION of two tables in MySQL

For this, you can use UNION. Let us first create a table −

mysql> create table DemoTable1(FirstName varchar(1000));
Query OK, 0 rows affected (1.22 sec)

Insert some records in the table using insert command −

mysql> insert into DemoTable1 values('John');
Query OK, 1 row affected (0.20 sec)

Display all records from the table using select statement −

mysql> select *from DemoTable1;

This will produce the following output −

+-----------+
| FirstName |
+-----------+
| John      |
+-----------+
1 row in set (0.02 sec)

Here is the query to create second the table −

mysql> create table DemoTable2(FirstName varchar(100));
Query OK, 0 rows affected (0.81 sec)

Insert some records in the table using insert command −

mysql> insert into DemoTable2 values('Chris');
Query OK, 1 row affected (0.21 sec)

Display all records from the table using select statement −

mysql> select *from DemoTable2;

This will produce the following output −

+-----------+
| FirstName |
+-----------+
| Chris    |
+-----------+
1 row in set (0.00 sec)

Following is the query for CREATE TABLE AS statement and displaying the union of two or more tables in it −

mysql> create table DemoTable3 AS
   (
      select FirstName, 'DemoTable1' AS `TABLE_NAME` from DemoTable1)
      union
   (
   select FirstName, 'DemoTable2' AS `TABLE_NAME` from DemoTable2);
Query OK, 2 rows affected (1.08 sec)
Records: 2 Duplicates: 0 Warnings: 0

Display all the records from the table DemoTable3 −

mysql> select *from DemoTable3;

This will produce the following output −

+-----------+--------------+
| FirstName | TABLE_NAME   |
+-----------+--------------+
| John      | DemoTable1   |
| Chris     | DemoTable2   |
+-----------+--------------+
2 rows in set (0.00 sec)

AmitDiwan

Published on 22-Aug-2019 10:54:03

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