# Join Example (Continue...)
__*INNER JOIN*__
__*Top-N Analysis*__
+ What are the top 5 planets with gravitational acceleration in the Solar system?
```10
tidb> SELECT
    -> p.name, p.gravity
    -> FROM ~!@planets p@!~
    -> JOIN ~!@stars s@!~
    -> ON p.sun_id = s.id
    -> WHERE s.name = 'Sun'
    -> ~!@ORDER BY p.gravity DESC@!~
    -> ~!@LIMIT 5@!~;
+---------+---------+
| name    | gravity |
+---------+---------+
| Jupiter |    23.1 |
| Neptune |    11.0 |
| Earth   |     9.8 |
| Saturn  |     9.0 |
| Venus   |     8.9 |
+---------+---------+
5 rows in set (0.01 sec)
```

------------------------------------------------------------
```
tidb> EXPLAIN SELECT
    -> p.name, p.gravity
    -> FROM planets p
    -> JOIN stars s
    -> ON p.sun_id = s.id
    -> WHERE s.name = 'Sun'
    -> ORDER BY p.gravity DESC
    -> LIMIT 5;
+-------------------------------+---------+-----------+---------------------------+--------------------------------------------------------------------+
| id                            | estRows | task      | access object             | operator info                                                      |
+-------------------------------+---------+-----------+---------------------------+--------------------------------------------------------------------+
| TopN_15                       | 0.00    | root      |                           | universe.planets.gravity:desc, offset:0, count:5                   |
| └─HashJoin_33                 | 0.00    | root      |                           | inner join, equal:[eq(universe.stars.id, universe.planets.sun_id)] |
|   ├─IndexReader_37(Build)     | 0.00    | root      |                           | index:IndexRangeScan_36                                            |
|   │ └─IndexRangeScan_36       | 0.00    | cop[tikv] | table:s, index:name(name) | range:["Sun","Sun"], keep order:false, stats:pseudo                |
|   └─TableReader_35(Probe)     | 10.00   | root      |                           | data:TableFullScan_34                                              |
|     └─TableFullScan_34        | 10.00   | cop[tikv] | table:p                   | keep order:false, stats:pseudo                                     |
+-------------------------------+---------+-----------+---------------------------+--------------------------------------------------------------------+
6 rows in set (0.00 sec)
```