# Querying Data From Multiple Tables
+ Some queries require data from more than one table
+ You can use a JOIN operation to combine data from different tables
+ To join tables, there should be a logical relationship between some of the columns in these tables
+ best practices: Using Table Name Aliases
+ Example tables:
```10
~!@test.a            test.b            test.c            test.d@!~
+------+------+   +------+------+   +------+------+   +------+------+
| id   | name |   | id   | name |   | id   | name |   | id   | name |
+------+------+   +------+------+   +------+------+   +------+------+
|    1 | AA   |   |    1 | BA   |   |    1 | CA   |   |    1 | DA   |
|    2 | AB   |   |    2 | BB   |   |    2 | CB   |   |    2 | DB   |
|    3 | AC   |   |    3 | BC   |   |    4 | CC   |   | ~!@NULL@!~ | DC   |
+------+------+   +------+------+   +------+------+   |    5 | ~!@NULL@!~ |
                                                      +------+------+
```

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