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# Status Codes

A sample solution as IoTDB requires registering the time series first before writing data is:

```
try {
    writeData();
} catch (SQLException e) {
  // the most case is that the time series does not exist
  if (e.getMessage().contains("exist")) {
      //However, using the content of the error message is not so efficient
      registerTimeSeries();
      //write data once again
      writeData();
  }
}

```

With Status Code, instead of writing codes like `if (e.getErrorMessage().contains("exist"))`, we can simply use `e.getErrorCode() == TSStatusCode.TIME_SERIES_NOT_EXIST_ERROR.getStatusCode()`.

Here is a list of Status Code and related message:

| Status Code | Status Type                            | Meanings                                                                                  |
|:------------|:---------------------------------------|:------------------------------------------------------------------------------------------|
| 200         | SUCCESS_STATUS                         |                                                                                           |
| 201         | INCOMPATIBLE_VERSION                   | Incompatible version                                                                      |
| 202         | CONFIGURATION_ERROR                    | Configuration error                                                                       |
| 203         | START_UP_ERROR                         | Meet error while starting                                                                 |
| 204         | SHUT_DOWN_ERROR                        | Meet error while shutdown                                                                 |
| 300         | UNSUPPORTED_OPERATION                  | Unsupported operation                                                                     |
| 301         | EXECUTE_STATEMENT_ERROR                | Execute statement error                                                                   |
| 302         | MULTIPLE_ERROR                         | Meet error when executing multiple statements                                             |
| 303         | ILLEGAL_PARAMETER                      | Parameter is illegal                                                                      |
| 304         | OVERLAP_WITH_EXISTING_TASK             | Current task has some conflict with existing tasks                                        |
| 305         | INTERNAL_SERVER_ERROR                  | Internal server error                                                                     |
| 306         | DISPATCH_ERROR                         | Meet error while dispatching                                                              |
| 400         | REDIRECTION_RECOMMEND                  | Recommend Client redirection                                                              |
| 500         | DATABASE_NOT_EXIST                     | Database does not exist                                                                   |
| 501         | DATABASE_ALREADY_EXISTS                | Database already exist                                                                    |
| 502         | SERIES_OVERFLOW                        | Series number exceeds the threshold                                                       |
| 503         | TIMESERIES_ALREADY_EXIST               | Timeseries already exists                                                                 |
| 504         | TIMESERIES_IN_BLACK_LIST               | Timeseries is being deleted                                                               |
| 505         | ALIAS_ALREADY_EXIST                    | Alias already exists                                                                      |
| 506         | PATH_ALREADY_EXIST                     | Path already exists                                                                       |
| 507         | METADATA_ERROR                         | Meet error when dealing with metadata                                                     |
| 508         | PATH_NOT_EXIST                         | Path does not exist                                                                       |
| 509         | ILLEGAL_PATH                           | Illegal path                                                                              |
| 510         | CREATE_TEMPLATE_ERROR                  | Create schema template error                                                              |
| 511         | DUPLICATED_TEMPLATE                    | Schema template is duplicated                                                             |
| 512         | UNDEFINED_TEMPLATE                     | Schema template is not defined                                                            |
| 513         | TEMPLATE_NOT_SET                       | Schema template is not set                                                                |
| 514         | DIFFERENT_TEMPLATE                     | Template is not consistent                                                                |
| 515         | TEMPLATE_IS_IN_USE                     | Template is in use                                                                        |
| 516         | TEMPLATE_INCOMPATIBLE                  | Template is not compatible                                                                |
| 517         | SEGMENT_NOT_FOUND                      | Segment not found                                                                         |
| 518         | PAGE_OUT_OF_SPACE                      | No enough space on schema page                                                            |
| 519         | RECORD_DUPLICATED                      | Record is duplicated                                                                      |
| 520         | SEGMENT_OUT_OF_SPACE                   | No enough space on schema segment                                                         |
| 521         | PBTREE_FILE_NOT_EXISTS                | PBTreeFile does not exist                                                                 |
| 522         | OVERSIZE_RECORD                        | Size of record exceeds the threshold of page of PBTreeFile                                |
| 523         | PBTREE_FILE_REDO_LOG_BROKEN           | PBTreeFile redo log has broken                                                            |
| 524         | TEMPLATE_NOT_ACTIVATED                 | Schema template is not activated                                                          |
| 526         | SCHEMA_QUOTA_EXCEEDED                  | Schema usage exceeds quota limit                                                          |
| 527  | MEASUREMENT_ALREADY_EXISTS_IN_TEMPLATE | Measurement already exists in schema template                                    | 
| 600         | SYSTEM_READ_ONLY                       | IoTDB system is read only                                                                 |
| 601         | STORAGE_ENGINE_ERROR                   | Storage engine related error                                                              |
| 602         | STORAGE_ENGINE_NOT_READY               | The storage engine is in recovery, not ready fore accepting read/write operation          |
| 603         | DATAREGION_PROCESS_ERROR               | DataRegion related error                                                                  |
| 604         | TSFILE_PROCESSOR_ERROR                 | TsFile processor related error                                                            |
| 605         | WRITE_PROCESS_ERROR                    | Writing data related error                                                                |
| 606         | WRITE_PROCESS_REJECT                   | Writing data rejected error                                                               |
| 607         | OUT_OF_TTL                             | Insertion time is less than TTL time bound                                                |
| 608         | COMPACTION_ERROR                       | Meet error while merging                                                                  |
| 609         | ALIGNED_TIMESERIES_ERROR               | Meet error in aligned timeseries                                                          |
| 610         | WAL_ERROR                              | WAL error                                                                                 |
| 611         | DISK_SPACE_INSUFFICIENT                | Disk space is insufficient                                                                |
| 700         | SQL_PARSE_ERROR                        | Meet error while parsing SQL                                                              |
| 701         | SEMANTIC_ERROR                         | SQL semantic error                                                                        |
| 702         | GENERATE_TIME_ZONE_ERROR               | Meet error while generating time zone                                                     |
| 703         | SET_TIME_ZONE_ERROR                    | Meet error while setting time zone                                                        |
| 704         | QUERY_NOT_ALLOWED                      | Query statements are not allowed error                                                    |
| 705         | LOGICAL_OPERATOR_ERROR                 | Logical operator related error                                                            |
| 706         | LOGICAL_OPTIMIZE_ERROR                 | Logical optimize related error                                                            |
| 707         | UNSUPPORTED_FILL_TYPE                  | Unsupported fill type related error                                                       |
| 708         | QUERY_PROCESS_ERROR                    | Query process related error                                                               |
| 709         | MPP_MEMORY_NOT_ENOUGH                  | Not enough memory for task execution in MPP                                               |
| 710         | CLOSE_OPERATION_ERROR                  | Meet error in close operation                                                             |
| 711         | TSBLOCK_SERIALIZE_ERROR                | TsBlock serialization error                                                               |
| 712         | INTERNAL_REQUEST_TIME_OUT              | MPP Operation timeout                                                                     |
| 713         | INTERNAL_REQUEST_RETRY_ERROR           | Internal operation retry failed                                                           |
| 714         | NO_SUCH_QUERY                          | Cannot find target query                                                                  |
| 715         | QUERY_WAS_KILLED                       | Query was killed when execute                                                             |
| 800         | UNINITIALIZED_AUTH_ERROR               | Failed to initialize auth module                                                          |
| 801         | WRONG_LOGIN_PASSWORD                   | Username or password is wrong                                                             |
| 802         | NOT_LOGIN                              | Not login                                                                                 |
| 803         | NO_PERMISSION                          | No permisstion to operate                                                                 |
| 804         | USER_NOT_EXIST                         | User not exists                                                                           |
| 805         | USER_ALREADY_EXIST                     | User already exists                                                                       |
| 806         | USER_ALREADY_HAS_ROLE                  | User already has target role                                                              |
| 807         | USER_NOT_HAS_ROLE                      | User not has target role                                                                  |
| 808         | ROLE_NOT_EXIST                         | Role not exists                                                                           |
| 809         | ROLE_ALREADY_EXIST                     | Role already exists                                                                       |
| 810         | ALREADY_HAS_PRIVILEGE                  | Already has privilege                                                                     |
| 811         | NOT_HAS_PRIVILEGE                      | Not has privilege                                                                         |
| 812         | CLEAR_PERMISSION_CACHE_ERROR           | Failed to clear permission cache                                                          |
| 813         | UNKNOWN_AUTH_PRIVILEGE                 | Unknown auth privilege                                                                    |
| 814         | UNSUPPORTED_AUTH_OPERATION             | Unsupported auth operation                                                                |
| 815         | AUTH_IO_EXCEPTION                      | IO Exception in auth module                                                               |
| 900         | MIGRATE_REGION_ERROR                   | Error when migrate region                                                                 |
| 901         | CREATE_REGION_ERROR                    | Create region error                                                                       |
| 902         | DELETE_REGION_ERROR                    | Delete region error                                                                       |
| 903         | PARTITION_CACHE_UPDATE_ERROR           | Update partition cache failed                                                             |
| 904         | CONSENSUS_NOT_INITIALIZED              | Consensus is not initialized and cannot provide service                                   |
| 905         | REGION_LEADER_CHANGE_ERROR             | Region leader migration failed                                                            |
| 906         | NO_AVAILABLE_REGION_GROUP              | Cannot find an available region group                                                     |
| 907         | LACK_DATA_PARTITION_ALLOCATION         | Lacked some data partition allocation result in the response                              |
| 1000        | DATANODE_ALREADY_REGISTERED            | DataNode already registered in cluster                                                    |
| 1001        | NO_ENOUGH_DATANODE                     | The number of DataNode is not enough, cannot remove DataNode or create enough replication |
| 1002        | ADD_CONFIGNODE_ERROR                   | Add ConfigNode error                                                                      |
| 1003        | REMOVE_CONFIGNODE_ERROR                | Remove ConfigNode error                                                                   |
| 1004        | DATANODE_NOT_EXIST                     | DataNode not exist error                                                                  |
| 1005        | DATANODE_STOP_ERROR                    | DataNode stop error                                                                       |
| 1006        | REMOVE_DATANODE_ERROR                  | Remove datanode failed                                                                    |
| 1007        | REGISTER_DATANODE_WITH_WRONG_ID        | The DataNode to be registered has incorrect register id                                   |
| 1008        | CAN_NOT_CONNECT_DATANODE               | Can not connect to DataNode                                                               |
| 1100        | LOAD_FILE_ERROR                        | Meet error while loading file                                                             |
| 1101        | LOAD_PIECE_OF_TSFILE_ERROR             | Error when load a piece of TsFile when loading                                            |
| 1102        | DESERIALIZE_PIECE_OF_TSFILE_ERROR      | Error when deserialize a piece of TsFile                                                  |
| 1103        | SYNC_CONNECTION_ERROR                  | Sync connection error                                                                     |
| 1104        | SYNC_FILE_REDIRECTION_ERROR            | Sync TsFile redirection error                                                             |
| 1105        | SYNC_FILE_ERROR                        | Sync TsFile error                                                                         |
| 1106        | CREATE_PIPE_SINK_ERROR                 | Failed to create a PIPE sink                                                              |
| 1107        | PIPE_ERROR                             | PIPE error                                                                                |
| 1108        | PIPESERVER_ERROR                       | PIPE server error                                                                         |
| 1109        | VERIFY_METADATA_ERROR                  | Meet error in validate timeseries schema                                                  |
| 1200        | UDF_LOAD_CLASS_ERROR                   | Error when loading UDF class                                                              |
| 1201        | UDF_DOWNLOAD_ERROR                     | DataNode cannot download UDF from ConfigNode                                              |
| 1202        | CREATE_UDF_ON_DATANODE_ERROR           | Error when create UDF on DataNode                                                         |
| 1203        | DROP_UDF_ON_DATANODE_ERROR             | Error when drop a UDF on DataNode                                                         |
| 1300        | CREATE_TRIGGER_ERROR                   | ConfigNode create trigger error                                                           |
| 1301        | DROP_TRIGGER_ERROR                     | ConfigNode delete Trigger error                                                           |
| 1302        | TRIGGER_FIRE_ERROR                     | Error when firing trigger                                                                 |
| 1303        | TRIGGER_LOAD_CLASS_ERROR               | Error when load class of trigger                                                          |
| 1304        | TRIGGER_DOWNLOAD_ERROR                 | Error when download trigger from ConfigNode                                               |
| 1305        | CREATE_TRIGGER_INSTANCE_ERROR          | Error when create trigger instance                                                        |
| 1306        | ACTIVE_TRIGGER_INSTANCE_ERROR          | Error when activate trigger instance                                                      |
| 1307        | DROP_TRIGGER_INSTANCE_ERROR            | Error when drop trigger instance                                                          |
| 1308        | UPDATE_TRIGGER_LOCATION_ERROR          | Error when move stateful trigger to new datanode                                          |
| 1400        | NO_SUCH_CQ                             | CQ task does not exist                                                                    |
| 1401        | CQ_ALREADY_ACTIVE                      | CQ is already active                                                                      |
| 1402        | CQ_AlREADY_EXIST                       | CQ is already exist                                                                       |
| 1403        | CQ_UPDATE_LAST_EXEC_TIME_ERROR         | CQ update last execution time failed                                                      |

> All exceptions are refactored in the latest version by extracting uniform message into exception classes. Different error codes are added to all exceptions. When an exception is caught and a higher-level exception is thrown, the error code will keep and pass so that users will know the detailed error reason.
A base exception class "ProcessException" is also added to be extended by all exceptions.