SQLite Joins
To combine records from two or more tables in a database, the SQLite Joins are used. The common values in the mentioned fields from the tables are fetched and displayed as the result.
Types of SQLite Joins:
SQLite supports three types of Joins, including,
- SQLite INNER JOIN
- SQLite OUTER JOIN
- SQLite CROSS JOIN
Example:
STUDENTS Table:
STUDENT_ID | STUDENT_NAME | STUDENT_SUBJECT |
1 | Tom | French |
2 | Jerry | Physics |
3 | Bruno | English |
TEACHERS Table:
ID | NAME | SALARY | SUBJECT |
1 | Jim | 10000 | Geology |
2 | John | 20000 | Geology |
3 | Watson | 15000 | Physics |
4 | Holmes | 25000 | Chemistry |
5 | Tony | 30000 | Physics |
SELECT ID, STUDENT_NAME, NAME, SUBJECT FROM STUDENTS INNER JOIN TEACHERS ON STUDENTS.STUDENT_SUBJECT = TEACHERS.SUBJECT; |
Output:
ID | STUDENT_NAME | NAME | SUBJECT |
3 | Tom | Watson | French |
5 | Jerry | Tony | Physics |
1 | Bruno | Jim | English |
Explanation:
In the above example, the records from the ID, NAME, and the SUBJECT Columns of the TEACHERS table and the STUDENT_NAME column of the STUDENTS table is fetched and joined where the value of the STUDENT_SUBJECT column of the STUDENTS table is equal to the SUBJECT column of the TEACHERS table.