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Add ORC output format

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Задокументировал вывод данных в ORC формате.
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Dmitriy 2021-03-24 00:08:07 +03:00
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docs/en/interfaces/formats.md
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@ -50,7 +50,7 @@ The supported formats are:
| [Parquet](#data-format-parquet) | ✔ | ✔ |
| [Arrow](#data-format-arrow) | ✔ | ✔ |
| [ArrowStream](#data-format-arrow-stream) | ✔ | ✔ |
| [ORC](#data-format-orc) | ✔ | ✗ |
| [ORC](#data-format-orc) | ✔ | ✔ |
| [RowBinary](#rowbinary) | ✔ | ✔ |
| [RowBinaryWithNamesAndTypes](#rowbinarywithnamesandtypes) | ✔ | ✔ |
| [Native](#native) | ✔ | ✔ |
@ -1284,36 +1284,37 @@ To exchange data with Hadoop, you can use [HDFS table engine](../engines/table-e
## ORC {#data-format-orc}
[Apache ORC](https://orc.apache.org/) is a columnar storage format widespread in the Hadoop ecosystem. You can only insert data in this format to ClickHouse.
[Apache ORC](https://orc.apache.org/) is a columnar storage format widespread in the [Hadoop](https://hadoop.apache.org/) ecosystem.
### Data Types Matching {#data_types-matching-3}
The table below shows supported data types and how they match ClickHouse [data types](../sql-reference/data-types/index.md) in `INSERT` queries.
The table below shows supported data types and how they match ClickHouse [data types](../sql-reference/data-types/index.md).
| ORC data type (`INSERT`) | ClickHouse data type |
|--------------------------|-----------------------------------------------------|
| `UINT8`, `BOOL` | [UInt8](../sql-reference/data-types/int-uint.md) |
| `INT8` | [Int8](../sql-reference/data-types/int-uint.md) |
| `UINT16` | [UInt16](../sql-reference/data-types/int-uint.md) |
| `INT16` | [Int16](../sql-reference/data-types/int-uint.md) |
| `UINT32` | [UInt32](../sql-reference/data-types/int-uint.md) |
| `INT32` | [Int32](../sql-reference/data-types/int-uint.md) |
| `UINT64` | [UInt64](../sql-reference/data-types/int-uint.md) |
| `INT64` | [Int64](../sql-reference/data-types/int-uint.md) |
| `FLOAT`, `HALF_FLOAT` | [Float32](../sql-reference/data-types/float.md) |
| `DOUBLE` | [Float64](../sql-reference/data-types/float.md) |
| `DATE32` | [Date](../sql-reference/data-types/date.md) |
| `DATE64`, `TIMESTAMP` | [DateTime](../sql-reference/data-types/datetime.md) |
| `STRING`, `BINARY` | [String](../sql-reference/data-types/string.md) |
| `DECIMAL` | [Decimal](../sql-reference/data-types/decimal.md) |
| ORC data type (`INSERT`) | ClickHouse data type | ORC data type (`SELECT`) |
|--------------------------|-----------------------------------------------------|--------------------------|
| `UINT8`, `BOOL` | [UInt8](../sql-reference/data-types/int-uint.md) | `UINT8` |
| `INT8` | [Int8](../sql-reference/data-types/int-uint.md) | `INT8` |
| `UINT16` | [UInt16](../sql-reference/data-types/int-uint.md) | `UINT16` |
| `INT16` | [Int16](../sql-reference/data-types/int-uint.md) | `INT16` |
| `UINT32` | [UInt32](../sql-reference/data-types/int-uint.md) | `UINT32` |
| `INT32` | [Int32](../sql-reference/data-types/int-uint.md) | `INT32` |
| `UINT64` | [UInt64](../sql-reference/data-types/int-uint.md) | `UINT64` |
| `INT64` | [Int64](../sql-reference/data-types/int-uint.md) | `INT64` |
| `FLOAT`, `HALF_FLOAT` | [Float32](../sql-reference/data-types/float.md) | `FLOAT` |
| `DOUBLE` | [Float64](../sql-reference/data-types/float.md) | `DOUBLE` |
| `DATE32` | [Date](../sql-reference/data-types/date.md) | `DATE32` |
| `DATE64`, `TIMESTAMP` | [DateTime](../sql-reference/data-types/datetime.md) | `TIMESTAMP` |
| `STRING`, `BINARY` | [String](../sql-reference/data-types/string.md) | `BINARY` |
| `DECIMAL` | [Decimal](../sql-reference/data-types/decimal.md) | `DECIMAL` |
| `-` | [Array](../sql-reference/data-types/array.md) | `LIST` |
ClickHouse supports configurable precision of the `Decimal` type. The `INSERT` query treats the ORC `DECIMAL` type as the ClickHouse `Decimal128` type.
ClickHouse supports configurable precision of the `Decimal` type. The `INSERT` or `SELECT` query treats the ORC `DECIMAL` type as the ClickHouse `Decimal128` type.
Unsupported ORC data types: `DATE32`, `TIME32`, `FIXED_SIZE_BINARY`, `JSON`, `UUID`, `ENUM`.
Unsupported ORC data types: `TIME32`, `FIXED_SIZE_BINARY`, `JSON`, `UUID`, `ENUM`.
The data types of ClickHouse table columns don’t have to match the corresponding ORC data fields. When inserting data, ClickHouse interprets data types according to the table above and then [casts](../sql-reference/functions/type-conversion-functions.md#type_conversion_function-cast) the data to the data type set for the ClickHouse table column.
### Inserting Data {#inserting-data-2}
### Inserting and Selecting Data {#inserting-and-selecting-data-1}
You can insert ORC data from a file into ClickHouse table by the following command:
@ -1321,6 +1322,12 @@ You can insert ORC data from a file into ClickHouse table by the following comma
$ cat filename.orc | clickhouse-client --query="INSERT INTO some_table FORMAT ORC"
```
You can select data from a ClickHouse table and save them into some file in the ORC format by the following command:
``` bash
$ clickhouse-client --query="SELECT * FROM {some_table} FORMAT ORC" > {filename.orc}
```
To exchange data with Hadoop, you can use [HDFS table engine](../engines/table-engines/integrations/hdfs.md).
## LineAsString {#lineasstring}