SQLite Union All Operator
The SQLite UNION ALL operator is used to combine the result of two or more SELECT statement without ignoring the duplicate rows.
In SQLite UNION ALL, the resultant table also includes the duplicate values. Otherwise, the same rule applies as Union.
We have two tables "STUDENT" and "DEPARTMENT".
The "STUDENT" table is having the following data:
The "DEPARTMENT" table is having the following data:
Example1: Return Single Field
This simple example returns only one field from multiple SELECT statements where the both fields have same data type.
Let's take the above two tables "STUDENT" and "DEPARTMENT" and select id from both table to make UNION ALL.
Example2: UNION ALL with Inner and Outer Join
Let's take the above two tables "STUDENT" and "DEPARTMENT" and make an inner join and outer join according to the below conditions along with UNION ALL Clause: