Starting from TDengine version 3.0, a built-in database called performance_schema has been provided, which stores performance-related statistical data. This section details the tables and structures within it.
Provides information about applications (clients) that connect to the cluster. You can also use SHOW APPS to query this information.
| # | Column Name | Data Type | Description |
|---|
| 1 | app_id | UBIGINT | Client ID |
| 2 | ip | BINARY(16) | Client address |
| 3 | pid | INT | Client process ID |
| 4 | name | BINARY(24) | Client name |
| 5 | start_time | TIMESTAMP | Client startup time |
| 6 | insert_req | UBIGINT | Number of insert requests |
| 7 | insert_row | UBIGINT | Number of rows inserted |
| 8 | insert_time | UBIGINT | Processing time of insert requests, in microseconds |
| 9 | insert_bytes | UBIGINT | Number of bytes in insert request message |
| 10 | fetch_bytes | UBIGINT | Number of bytes in query results |
| 11 | query_time | UBIGINT | Processing time for query requests |
| 12 | slow_query | UBIGINT | Number of slow queries (processing time >= 3 seconds) |
| 13 | total_req | UBIGINT | Total number of requests |
| 14 | current_req | UBIGINT | Number of currently processed requests |
| 15 | last_access | TIMESTAMP | Last update time |
Provides information about database connections. You can also use SHOW CONNECTIONS to query this information.
| # | Column Name | Data Type | Description |
|---|
| 1 | conn_id | INT | Connection ID |
| 2 | user | BINARY(24) | Username |
| 3 | app | BINARY(24) | Client name |
| 4 | pid | UINT | Process ID of the client that initiated this connection |
| 5 | end_point | BINARY(128) | Client address |
| 6 | login_time | TIMESTAMP | Login time |
| 7 | last_access | TIMESTAMP | Last update time |
Provides information about currently executing SQL statements. You can also use SHOW QUERIES to query this information.
| # | Column Name | Data Type | Description |
|---|
| 1 | kill_id | UBIGINT | ID used to stop the query |
| 2 | query_id | INT | Query ID |
| 3 | conn_id | UINT | Connection ID |
| 4 | app | BINARY(24) | App name |
| 5 | pid | INT | App process ID on the host |
| 6 | user | BINARY(24) | Username |
| 7 | end_point | BINARY(16) | Client address |
| 8 | create_time | TIMESTAMP | Creation time |
| 9 | exec_usec | BIGINT | Execution time |
| 10 | stable_query | BOOL | Indicates if it is a supertable query |
| 11 | sub_num | INT | Number of subqueries |
| 12 | sub_status | BINARY(1000) | Subquery status |
| 13 | sql | BINARY(1024) | SQL statement |
| # | Column Name | Data Type | Description |
|---|
| 1 | consumer_id | BIGINT | Unique ID of the consumer |
| 2 | consumer_group | BINARY(192) | Consumer group |
| 3 | client_id | BINARY(192) | User-defined string, displayed by specifying client_id when creating the consumer |
| 4 | status | BINARY(20) | Current status of the consumer. Status includes: ready (available), lost (connection lost), rebalancing (vgroup allocation in progress), unknown (unknown state) |
| 5 | topics | BINARY(204) | Subscribed topics. If multiple topics are subscribed, they are displayed in multiple rows |
| 6 | up_time | TIMESTAMP | Time of first connection to taosd |
| 7 | subscribe_time | TIMESTAMP | Time of last subscription initiation |
| 8 | rebalance_time | TIMESTAMP | Time of last rebalance trigger |
| # | Column Name | Data Type | Description |
|---|
| 1 | id | INT | ID of the ongoing transaction |
| 2 | create_time | TIMESTAMP | Creation time of the transaction |
| 3 | stage | BINARY(12) | Current stage of the transaction, usually redoAction, undoAction, commit |
| 4 | db1 | BINARY(64) | Name of database 1 that conflicts with this transaction |
| 5 | db2 | BINARY(64) | Name of database 2 that conflicts with this transaction |
| 6 | failed_times | INT | Total number of times the transaction execution failed |
| 7 | last_exec_time | TIMESTAMP | Last execution time of the transaction |
| 8 | last_action_info | BINARY(511) | Details of the last execution failure of the transaction |
| # | Column Name | Data Type | Description |
|---|
| 1 | sma_name | BINARY(192) | Name of the time-range-wise SMA |
| 2 | create_time | TIMESTAMP | Creation time of the SMA |
| 3 | stable_name | BINARY(192) | Name of the supertable to which the SMA belongs |
| 4 | vgroup_id | INT | Name of the exclusive vgroup for the SMA |
