ClickHouse/docs/en/sql-reference/table-functions/s3.md

---
toc_priority: 45
toc_title: s3
---

# s3 {#s3}

Provides table-like interface to select/insert files in S3. This table function is similar to [hdfs](../../sql-reference/table-functions/hdfs.md).

``` sql
s3(path, [aws_access_key_id, aws_secret_access_key,] format, structure, [compression])
```

**Input parameters**

-   `path` — Bucket url with path to file. Supports following wildcards in readonly mode: *, ?, {abc,def} and {N..M} where N, M — numbers, `’abc’, ‘def’ — strings.
-   `format` — The [format](../../interfaces/formats.md#formats) of the file.
-   `structure` — Structure of the table. Format `'column1_name column1_type, column2_name column2_type, ...'`.
-   `compression` — Parameter is optional. Supported values: none, gzip/gz, brotli/br, xz/LZMA, zstd/zst. By default, it will autodetect compression by file extension.

**Returned value**

A table with the specified structure for reading or writing data in the specified file.

**Example**

Table from S3 file `https://storage.yandexcloud.net/my-test-bucket-768/data.csv` and selection of the first two rows from it:

``` sql
SELECT *
FROM s3('https://storage.yandexcloud.net/my-test-bucket-768/data.csv', 'CSV', 'column1 UInt32, column2 UInt32, column3 UInt32')
LIMIT 2
```

``` text
┌─column1─┬─column2─┬─column3─┐
│       1 │       2 │       3 │
│       3 │       2 │       1 │
└─────────┴─────────┴─────────┘
```

The similar but from file with `gzip` compression:

``` sql
SELECT *
FROM s3('https://storage.yandexcloud.net/my-test-bucket-768/data.csv.gz', 'CSV', 'column1 UInt32, column2 UInt32, column3 UInt32', 'gzip')
LIMIT 2
```

``` text
┌─column1─┬─column2─┬─column3─┐
│       1 │       2 │       3 │
│       3 │       2 │       1 │
└─────────┴─────────┴─────────┘
```

**Globs in path**

Multiple path components can have globs. For being processed file should exists and matches to the whole path pattern (not only suffix or prefix).

-   `*` — Substitutes any number of any characters except `/` including empty string.
-   `?` — Substitutes any single character.
-   `{some_string,another_string,yet_another_one}` — Substitutes any of strings `'some_string', 'another_string', 'yet_another_one'`.
-   `{N..M}` — Substitutes any number in range from N to M including both borders. N and M can have leading zeroes e.g. `000..078`.

Constructions with `{}` are similar to the [remote table function](../../sql-reference/table-functions/remote.md)).

**Example**

1.  Suppose that we have several files with following URIs on S3:

-   ‘https://storage.yandexcloud.net/my-test-bucket-768/some_prefix/some_file_1.csv’
-   ‘https://storage.yandexcloud.net/my-test-bucket-768/some_prefix/some_file_2.csv’
-   ‘https://storage.yandexcloud.net/my-test-bucket-768/some_prefix/some_file_3.csv’
-   ‘https://storage.yandexcloud.net/my-test-bucket-768/some_prefix/some_file_4.csv’
-   ‘https://storage.yandexcloud.net/my-test-bucket-768/another_prefix/some_file_1.csv’
-   ‘https://storage.yandexcloud.net/my-test-bucket-768/another_prefix/some_file_2.csv’
-   ‘https://storage.yandexcloud.net/my-test-bucket-768/another_prefix/some_file_3.csv’
-   ‘https://storage.yandexcloud.net/my-test-bucket-768/another_prefix/some_file_4.csv’

2.  Query the amount of rows in files end with number from 1 to 3:

<!-- -->

``` sql
SELECT count(*)
FROM s3('https://storage.yandexcloud.net/my-test-bucket-768/{some,another}_prefix/some_file_{1..3}.csv', 'CSV', 'name String, value UInt32')
```

``` text
┌─count()─┐
│      18 │
└─────────┘
```

3.  Query the amount of rows in all files of these two directories:

<!-- -->

``` sql
SELECT count(*)
FROM s3('https://storage.yandexcloud.net/my-test-bucket-768/{some,another}_prefix/*', 'CSV', 'name String, value UInt32')
```

``` text
┌─count()─┐
│      24 │
└─────────┘
```


!!! warning "Warning"
    If your listing of files contains number ranges with leading zeros, use the construction with braces for each digit separately or use `?`.

**Example**

Query the data from files named `file-000.csv`, `file-001.csv`, … , `file-999.csv`:

``` sql
SELECT count(*)
FROM s3('https://storage.yandexcloud.net/my-test-bucket-768/big_prefix/file-{000..999}.csv', 'CSV', 'name String, value UInt32')
```

``` text
┌─count()─┐
│      12 │
└─────────┘
```

**Data insert**

The S3 table function may be used for data insert as well.

**Example**

Insert a data into file `test-data.csv.gz`:

``` sql
INSERT INTO s3('https://storage.yandexcloud.net/my-test-bucket-768/test-data.csv.gz', 'CSV', 'name String, value UInt32', 'gzip')
VALUES ('test-data', 1), ('test-data-2', 2)
```

Insert a data into file `test-data.csv.gz` from existing table:

``` sql
INSERT INTO s3('https://storage.yandexcloud.net/my-test-bucket-768/test-data.csv.gz', 'CSV', 'name String, value UInt32', 'gzip')
SELECT name, value FROM existing_table
```

## Virtual Columns {#virtual-columns}

-   `_path` — Path to the file.
-   `_file` — Name of the file.

## S3-related settings {#settings}

The following settings can be set before query execution or placed into configuration file.

-   `s3_max_single_part_upload_size` — Default value is `64Mb`. The maximum size of object to upload using singlepart upload to S3.
-   `s3_min_upload_part_size` — Default value is `512Mb`. The minimum size of part to upload during multipart upload to [S3 Multipart upload](https://docs.aws.amazon.com/AmazonS3/latest/dev/uploadobjusingmpu.html).
-   `s3_max_redirects` — Default value is `10`. Max number of S3 redirects hops allowed.

Security consideration: if malicious user can specify arbitrary S3 URLs, `s3_max_redirects` must be set to zero to avoid [SSRF](https://en.wikipedia.org/wiki/Server-side_request_forgery) attacks; or alternatively, `remote_host_filter` must be specified in server configuration.

**See Also**

-   [Virtual columns](https://clickhouse.tech/docs/en/operations/table_engines/#table_engines-virtual_columns)

[Original article](https://clickhouse.tech/docs/en/query_language/table_functions/s3/) <!--hide-->