QL UNION ALL is query that allows you to select related information from 2 tables, the result is different from the UNION statement. It return all the record from SELECT statement that used.
UNION ALL selects all rows from each table and combines them into a single table.
The syntax is as follows:
SELECT [COLUMN NAME 1], [COLUMN NAME 2],… FROM [TABLE NAME 1]
UNION ALL
SELECT [COLUMN NAME 1], [COLUMN NAME 2],… FROM [TABLE NAME 2]
EXAMPLE :
We have 2 table name GamesScores, GameScores_new.
Table GameScores
| PlayerName | Department | Scores |
| Jason | IT | 3000 |
| Irene | IT | 1500 |
| Jane | Marketing | 1000 |
| David | Marketing | 2500 |
| Paul | HR | 2000 |
| James | HR | 2000 |
Table GameScores_new
| PlayerName | Department | Scores |
| Jason | IT | 3000 |
| David | Marketing | 2500 |
| Paul | HR | 2000 |
| James | HR | 2000 |
SQL statement :
SELECT PlayerName FROM GameScores
UNION ALL
SELECT PlayerName FROM GameScores_new
Result:
| PlayerName |
| Jason |
| Irene |
| Jane |
| David |
| Paul |
| James |
| Jason |
| David |
| Paul |
| James |