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mysql> SHOW INDEX FROM taxation;
+----------+------------+----------+--------------+------------------+-----------+-------------+----------+--------+------+------------+---------+
| Table    | Non_unique | Key_name | Seq_in_index | Column_name      | Collation | Cardinality | Sub_part | Packed | Null | Index_type | Comment |
+----------+------------+----------+--------------+------------------+-----------+-------------+----------+--------+------+------------+---------+
| taxation |          0 | PRIMARY  |            1 | called_number    | A         |      654668 |     NULL | NULL   |      | BTREE      |         |
| taxation |          0 | PRIMARY  |            2 | call_start       | A         |     1309336 |     NULL | NULL   |      | BTREE      |         |
| taxation |          0 | PRIMARY  |            3 | duration         | A         |     1309336 |     NULL | NULL   |      | BTREE      |         |
| taxation |          0 | PRIMARY  |            4 | id_route         | A         |     1309336 |     NULL | NULL   |      | BTREE      |         |
| taxation |          0 | PRIMARY  |            5 | source_peer_name | A         |     1309336 |     NULL | NULL   |      | BTREE      |         |
| taxation |          0 | PRIMARY  |            6 | gateway_name     | A         |     1309336 |     NULL | NULL   |      | BTREE      |         |
+----------+------------+----------+--------------+------------------+-----------+-------------+----------+--------+------+------------+---------+
6 rows in set (0.00 sec)

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