--- sidebar_position: 37 sidebar_label: file --- # file Creates a table from a file. This table function is similar to [url](../../sql-reference/table-functions/url.md) and [hdfs](../../sql-reference/table-functions/hdfs.md) ones. `file` function can be used in `SELECT` and `INSERT` queries on data in [File](../../engines/table-engines/special/file.md) tables. **Syntax** ``` sql file(path, format, structure) ``` **Parameters** - `path` — The relative path to the file from [user_files_path](../../operations/server-configuration-parameters/settings.md#server_configuration_parameters-user_files_path). Path to file support following globs in read-only 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, ...'`. **Returned value** A table with the specified structure for reading or writing data in the specified file. **Examples** Setting `user_files_path` and the contents of the file `test.csv`: ``` bash $ grep user_files_path /etc/clickhouse-server/config.xml /var/lib/clickhouse/user_files/ $ cat /var/lib/clickhouse/user_files/test.csv 1,2,3 3,2,1 78,43,45 ``` Getting data from a table in `test.csv` and selecting the first two rows from it: ``` sql SELECT * FROM file('test.csv', 'CSV', 'column1 UInt32, column2 UInt32, column3 UInt32') LIMIT 2; ``` ``` text ┌─column1─┬─column2─┬─column3─┐ │ 1 │ 2 │ 3 │ │ 3 │ 2 │ 1 │ └─────────┴─────────┴─────────┘ ``` Getting the first 10 lines of a table that contains 3 columns of [UInt32](../../sql-reference/data-types/int-uint.md) type from a CSV file: ``` sql SELECT * FROM file('test.csv', 'CSV', 'column1 UInt32, column2 UInt32, column3 UInt32') LIMIT 10; ``` Inserting data from a file into a table: ``` sql INSERT INTO FUNCTION file('test.csv', 'CSV', 'column1 UInt32, column2 UInt32, column3 UInt32') VALUES (1, 2, 3), (3, 2, 1); SELECT * FROM file('test.csv', 'CSV', 'column1 UInt32, column2 UInt32, column3 UInt32'); ``` ``` text ┌─column1─┬─column2─┬─column3─┐ │ 1 │ 2 │ 3 │ │ 3 │ 2 │ 1 │ └─────────┴─────────┴─────────┘ ``` ## Globs in Path Multiple path components can have globs. For being processed file must exist and match 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. Constructions with `{}` are similar to the [remote](remote.md) table function. **Example** Suppose we have several files with the following relative paths: - 'some_dir/some_file_1' - 'some_dir/some_file_2' - 'some_dir/some_file_3' - 'another_dir/some_file_1' - 'another_dir/some_file_2' - 'another_dir/some_file_3' Query the number of rows in these files: ``` sql SELECT count(*) FROM file('{some,another}_dir/some_file_{1..3}', 'TSV', 'name String, value UInt32'); ``` Query the number of rows in all files of these two directories: ``` sql SELECT count(*) FROM file('{some,another}_dir/*', 'TSV', 'name String, value UInt32'); ``` :::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 `file000`, `file001`, … , `file999`: ``` sql SELECT count(*) FROM file('big_dir/file{0..9}{0..9}{0..9}', 'CSV', 'name String, value UInt32'); ``` ## Virtual Columns - `_path` — Path to the file. - `_file` — Name of the file. **See Also** - [Virtual columns](../../engines/table-engines/index.md#table_engines-virtual_columns) [Original article](https://clickhouse.com/docs/en/sql-reference/table-functions/file/)