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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|
|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 number exceeds the threshold|
|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|SCHEMA_FILE_NOT_EXISTS|SchemaFile does not exist|
|522|OVERSIZE_RECORD|Size of record exceeds the threshold of page of SchemaFile|
|523|SCHEMA_FILE_REDO_LOG_BROKEN|SchemaFile redo log has broken|
|524|TEMPLATE_NOT_ACTIVATED|Schema template is not activated|
|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|
|800|AUTHENTICATION_ERROR|Error in authentication|
|801|WRONG_LOGIN_PASSWORD|Username or password is wrong|
|802|NOT_LOGIN|Has not logged in|
|803|NO_PERMISSION|No permissions for this operation, please add privilege|
|804|UNINITIALIZED_AUTH_ERROR|Uninitialized authorizer|
|805|USER_NOT_EXIST|User does not exist|
|806|ROLE_NOT_EXIST|Role does not exist|
|807|CLEAR_PERMISSION_CACHE_ERROR|Error when clear the permission cache|
|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|
|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_REMOVED_DATANODE|The DataNode to be registered is removed before|
|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|CREATE_PIPE_SINK_ERROR|Failed to create a PIPE sink|
|1104|PIPE_ERROR|PIPE error|
|1105|PIPESERVER_ERROR|PIPE server error|
|1106|SYNC_CONNECTION_ERROR|Meet error while sync connecting|
|1107|SYNC_FILE_REDIRECTION_ERROR|Sync TsFile redirection error|
|1108|SYNC_FILE_ERROR|Sync TsFile 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.