The SHOW INDEX statement returns index information for a table or database.
Required privileges
The user must have any privilege on the target table or database.
Aliases
In CockroachDB, the following are aliases for SHOW INDEX:
- SHOW INDEXES
- SHOW KEYS
Synopsis
Parameters
| Parameter | Description | 
|---|---|
| table_name | The name of the table for which to show indexes. | 
| database_name | The name of the database for which to show indexes. | 
Response
The following fields are returned for each column in each index.
| Field | Description | 
|---|---|
| table_name | The name of the table. | 
| index_name | The name of the index. | 
| non_unique | Whether values in the indexed column are unique. Possible values: trueorfalse. | 
| seq_in_index | The position of the column in the index, starting with 1. | 
| column_name | The indexed column. | 
| direction | How the column is sorted in the index. Possible values: ASCorDESCfor indexed columns;N/Afor stored columns. | 
| storing | Whether the STORINGclause was used to index the column during index creation. Possible values:trueorfalse. | 
| implicit | Whether the column is part of the index despite not being explicitly included during index creation. Possible values: trueorfalsePrimary key columns are the only columns implicitly included in secondary indexes. The inclusion of primary key columns improves performance when retrieving columns not in the index. | 
A column is in the primary key if the value of the index_name column is primary and value of the storing column is false.
Example
Setup
The following examples use MovR, a fictional vehicle-sharing application, to demonstrate CockroachDB SQL statements. For more information about the MovR example application and dataset, see MovR: A Global Vehicle-sharing App.
To follow along, run cockroach demo to start a temporary, in-memory cluster with the movr dataset preloaded:
$ cockroach demo
Show indexes for a table
> CREATE INDEX ON users (name);
> SHOW INDEX FROM users;
  table_name |   index_name   | non_unique | seq_in_index | column_name | direction | storing | implicit
-------------+----------------+------------+--------------+-------------+-----------+---------+-----------
  users      | primary        |   false    |            1 | city        | ASC       |  false  |  false
  users      | primary        |   false    |            2 | id          | ASC       |  false  |  false
  users      | primary        |   false    |            3 | name        | N/A       |  true   |  false
  users      | primary        |   false    |            4 | address     | N/A       |  true   |  false
  users      | primary        |   false    |            5 | credit_card | N/A       |  true   |  false
  users      | users_name_idx |    true    |            1 | name        | ASC       |  false  |  false
  users      | users_name_idx |    true    |            2 | city        | ASC       |  false  |   true
  users      | users_name_idx |    true    |            3 | id          | ASC       |  false  |   true
(8 rows)
In this example, the columns where the value of the index_name column is primary and value of the storing column is false, and thus are in the primary key, are city and id.
Show indexes for a database
> SHOW INDEXES FROM DATABASE movr;
          table_name         |                  index_name                   | non_unique | seq_in_index |   column_name    | direction | storing | implicit
-----------------------------+-----------------------------------------------+------------+--------------+------------------+-----------+---------+-----------
  users                      | primary                                       |   false    |            1 | city             | ASC       |  false  |  false
  users                      | primary                                       |   false    |            2 | id               | ASC       |  false  |  false
  users                      | primary                                       |   false    |            3 | name             | N/A       |  true   |  false
  users                      | primary                                       |   false    |            4 | address          | N/A       |  true   |  false
  users                      | primary                                       |   false    |            5 | credit_card      | N/A       |  true   |  false
  users                      | users_name_idx                                |    true    |            1 | name             | ASC       |  false  |  false
  users                      | users_name_idx                                |    true    |            2 | city             | ASC       |  false  |   true
  users                      | users_name_idx                                |    true    |            3 | id               | ASC       |  false  |   true
  vehicles                   | primary                                       |   false    |            1 | city             | ASC       |  false  |  false
  vehicles                   | primary                                       |   false    |            2 | id               | ASC       |  false  |  false
  vehicles                   | primary                                       |   false    |            3 | type             | N/A       |  true   |  false
  vehicles                   | primary                                       |   false    |            4 | owner_id         | N/A       |  true   |  false
  vehicles                   | primary                                       |   false    |            5 | creation_time    | N/A       |  true   |  false
  vehicles                   | primary                                       |   false    |            6 | status           | N/A       |  true   |  false
  vehicles                   | primary                                       |   false    |            7 | current_location | N/A       |  true   |  false
  vehicles                   | primary                                       |   false    |            8 | ext              | N/A       |  true   |  false
  vehicles                   | vehicles_auto_index_fk_city_ref_users         |    true    |            1 | city             | ASC       |  false  |  false
  vehicles                   | vehicles_auto_index_fk_city_ref_users         |    true    |            2 | owner_id         | ASC       |  false  |  false
  vehicles                   | vehicles_auto_index_fk_city_ref_users         |    true    |            3 | id               | ASC       |  false  |   true
  rides                      | primary                                       |   false    |            1 | city             | ASC       |  false  |  false
  rides                      | primary                                       |   false    |            2 | id               | ASC       |  false  |  false
  rides                      | primary                                       |   false    |            3 | vehicle_city     | N/A       |  true   |  false
  rides                      | primary                                       |   false    |            4 | rider_id         | N/A       |  true   |  false
  rides                      | primary                                       |   false    |            5 | vehicle_id       | N/A       |  true   |  false
  rides                      | primary                                       |   false    |            6 | start_address    | N/A       |  true   |  false
  rides                      | primary                                       |   false    |            7 | end_address      | N/A       |  true   |  false
  rides                      | primary                                       |   false    |            8 | start_time       | N/A       |  true   |  false
  rides                      | primary                                       |   false    |            9 | end_time         | N/A       |  true   |  false
  rides                      | primary                                       |   false    |           10 | revenue          | N/A       |  true   |  false
  rides                      | rides_auto_index_fk_city_ref_users            |    true    |            1 | city             | ASC       |  false  |  false
  rides                      | rides_auto_index_fk_city_ref_users            |    true    |            2 | rider_id         | ASC       |  false  |  false
  rides                      | rides_auto_index_fk_city_ref_users            |    true    |            3 | id               | ASC       |  false  |   true
  rides                      | rides_auto_index_fk_vehicle_city_ref_vehicles |    true    |            1 | vehicle_city     | ASC       |  false  |  false
  rides                      | rides_auto_index_fk_vehicle_city_ref_vehicles |    true    |            2 | vehicle_id       | ASC       |  false  |  false
  rides                      | rides_auto_index_fk_vehicle_city_ref_vehicles |    true    |            3 | city             | ASC       |  false  |   true
  rides                      | rides_auto_index_fk_vehicle_city_ref_vehicles |    true    |            4 | id               | ASC       |  false  |   true
  vehicle_location_histories | primary                                       |   false    |            1 | city             | ASC       |  false  |  false
  vehicle_location_histories | primary                                       |   false    |            2 | ride_id          | ASC       |  false  |  false
  vehicle_location_histories | primary                                       |   false    |            3 | timestamp        | ASC       |  false  |  false
  vehicle_location_histories | primary                                       |   false    |            4 | lat              | N/A       |  true   |  false
  vehicle_location_histories | primary                                       |   false    |            5 | long             | N/A       |  true   |  false
  promo_codes                | primary                                       |   false    |            1 | code             | ASC       |  false  |  false
  promo_codes                | primary                                       |   false    |            2 | description      | N/A       |  true   |  false
  promo_codes                | primary                                       |   false    |            3 | creation_time    | N/A       |  true   |  false
  promo_codes                | primary                                       |   false    |            4 | expiration_time  | N/A       |  true   |  false
  promo_codes                | primary                                       |   false    |            5 | rules            | N/A       |  true   |  false
  user_promo_codes           | primary                                       |   false    |            1 | city             | ASC       |  false  |  false
  user_promo_codes           | primary                                       |   false    |            2 | user_id          | ASC       |  false  |  false
  user_promo_codes           | primary                                       |   false    |            3 | code             | ASC       |  false  |  false
  user_promo_codes           | primary                                       |   false    |            4 | timestamp        | N/A       |  true   |  false
  user_promo_codes           | primary                                       |   false    |            5 | usage_count      | N/A       |  true   |  false
(51 rows)