union all and union code example

Example 1: what is the difference between union and union all

UNION ALL:
COMBINES THE RESULT OF 2 QUERY AND
DOESN'T REMOVE DUPLICATE ROWS
AND DOESN'T SORT BY FIRST COLUMN

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

Example 2: union vs union all in sql

UNION ALL:
COMBINES THE RESULT OF 2 QUERY AND
DOESN'T REMOVE DUPLICATE ROWS
AND DOESN'T SORT BY FIRST COLUMN

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

Example 3: union all in sql

UNION ALL:
COMBINES THE RESULT OF 2 QUERY AND
DOESN'T REMOVE DUPLICATE ROWS
AND DOESN'T SORT BY FIRST COLUMN