What is union in sql

Sql union

-- UNION: distinct values (slower)
SELECT emp_name AS name from employees
UNION       
SELECT cust_name AS name from customers;

-- UNION ALL: keeps duplicates (faster)
SELECT emp_name AS name from employees
UNION ALL      
SELECT cust_name AS name from customers;

Union SQL

SQL> SELECT  ID, NAME, AMOUNT, DATE
   FROM CUSTOMERS
   LEFT JOIN ORDERS
   ON CUSTOMERS.ID = ORDERS.CUSTOMER_ID
UNION
   SELECT  ID, NAME, AMOUNT, DATE
   FROM CUSTOMERS
   RIGHT JOIN ORDERS
   ON CUSTOMERS.ID = ORDERS.CUSTOMER_ID;

Source: tutorialspoint.com

What is union in sql

UNION:
COMBINES THE RESULT OF 2 QUERY AND
REMOVES DUPLICATE ROWS AND
SORTS BY FIRST COLUMN

-2

Similar codes

11 votes212 views2 answers
How to import mysql database command line
SQL
0 vote195 views1 answer
Group_concat only returns one row
SQL
4 votes201 views4 answers
What is primary key
SQL
0 vote198 views1 answer
Oracle index hint
SQL
2 votes207 views1 answer
Sqlserver: how to search a table used in particular stored procedure
SQL
3 votes213 views1 answer
Null sql
SQL
7 votes203 views1 answer
Postgres base size
SQL
0 vote195 views1 answer
Go install mysql
SQL
0 vote192 views1 answer
Mysql get 2nd value in comma separated list
SQL
1 vote231 views1 answer
Mysql last year
SQL