In This Article, You Will Know About SQL Self JOIN.
SQL Self JOIN – Before moving ahead, let’s know a bit about SQL FULL JOIN.
Table of Contents
The SQL Self Join is used to join a table with itself as if it were given as two tables.
Syntax
SELECT a. Column_name, b.Column_name…
FROM table1 A1, table1 A2
WHERE a.same_column_name = b.same_column_name;
Note: A1 and A2 are the aliases for the table name.
Example Database
Table name: Data
S.No | Name | Class | Section | Address |
1 | Alex | 5 | A | NY-10 |
2 | Rolex | 6 | B | LA-12 |
3 | Salex | 7 | C | GR-15 |
4 | Jalex | 8 | D | SP-18 |
5 | Kalex | 9 | E | WS-20 |
SQL Self Join
Example: Use the SQL Self Join to join a table with itself.
SELECT a.Name, b.Class, a.Address
FROM Data a, Data b
WHERE a.Address <> b.Address;
Example: Use the SQL Self Join to join a table with itself, ordered by Address.
SELECT a.Name, b.Class, a.Address
FROM Data a, Data b
WHERE a.Address <> b.Address
ORDER BY a.Address;
If you find anything incorrect in the above-discussed topic and have further questions, please comment below.
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