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## PutIoTDB

### Properties of PutIoTDB

| property      | description                                                  | default value | necessary |
| ------------- | ------------------------------------------------------------ | ------------- | --------- |
| Host          | The host of IoTDB.                                           | null          | true      |
| Port          | The port of IoTDB.                                           | 6667          | true      |
| Username      | Username to access the IoTDB.                                | null          | true      |
| Password      | Password to access the IoTDB.                                | null          | true      |
| Record Reader | Specifies the type of Record Reader controller service to use <br />for parsing the incoming data and determining the schema. | null          | true      |
| Schema        | The schema that IoTDB needs doesn't support good by NiFi.<br/>Therefore, you can define the schema here. <br />Besides, you can set encoding type and compression type by this method.<br />If you don't set this property, the inferred schema will be used.<br /> It can be updated by expression language. | null          | false     |
| Aligned       | Whether using aligned interface?  It can be updated by expression language. | false         | false     |
| MaxRowNumber  | Specifies the max row number of each tablet.  It can be updated by expression language. | 1024          | false     |

### Inferred Schema of Flowfile

There are a couple of rules about flowfile:

1. The flowfile can be read by `Record Reader`.
2. The schema of flowfile must contains a field `Time`, and it must be the first.
3. The data type of time must be `STRING` or `LONG`.
4. Fields excepted time must start with `root.`.
5. The supported data types are `INT`, `LONG`, `FLOAT`, `DOUBLE`, `BOOLEAN`, `TEXT`.

### Convert Schema by property

As mentioned above, converting schema by property which is more flexible and stronger than inferred schema. 

The structure of property `Schema`:

```json
{
	"timeType": "LONG",
	"fields": [{
		"tsName": "root.sg.d1.s1",
		"dataType": "INT32",
		"encoding": "RLE",
		"compressionType": "GZIP"
	}, {
		"tsName": "root.sg.d1.s2",
		"dataType": "INT64",
		"encoding": "RLE",
		"compressionType": "GZIP"
	}]
}
```

**Note**

1. The first column must be `Time`. The rest must be arranged in the same order as in `field` of JSON.
1. The JSON of schema must contain `timeType` and `fields`.
2. There are only two options `LONG` and `STRING` for `timeType`.
3. The columns `tsName` and `dataType` must be set.
4. The tsName must start with `root.`.
5. The supported `dataTypes` are `INT32`, `INT64`, `FLOAT`, `DOUBLE`, `BOOLEAN`, `TEXT`.
6. The supported `encoding` are `PLAIN`, `DICTIONARY`, `RLE`, `DIFF`, `TS_2DIFF`, `BITMAP`, `GORILLA_V1`, `REGULAR`, `GORILLA`.
7. The supported `compressionType` are `UNCOMPRESSED`, `SNAPPY`, `GZIP`, `LZO`, `SDT`, `PAA`, `PLA`, `LZ4`.

## Relationships

| relationship | description                                          |
| ------------ | ---------------------------------------------------- |
| success      | Data can be written correctly or flow file is empty. |
| failure      | The shema or flow file is abnormal.                  |
