ClickHouse/docs/en/operations/utilities/clickhouse-local.md
2022-12-05 17:28:03 +00:00

125 lines
4.5 KiB
Markdown
Raw Blame History

This file contains ambiguous Unicode characters

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

---
slug: /en/operations/utilities/clickhouse-local
sidebar_position: 60
sidebar_label: clickhouse-local
---
# clickhouse-local
The `clickhouse-local` program enables you to perform fast processing on local files, without having to deploy and configure the ClickHouse server.
Accepts data that represent tables and queries them using [ClickHouse SQL dialect](../../sql-reference/).
`clickhouse-local` uses the same core as ClickHouse server, so it supports most of the features and the same set of formats and table engines.
By default `clickhouse-local` does not have access to data on the same host, but it supports loading server configuration using `--config-file` argument.
:::warning
It is not recommended to load production server configuration into `clickhouse-local` because data can be damaged in case of human error.
:::
For temporary data, a unique temporary data directory is created by default.
## Usage {#usage}
Basic usage:
``` bash
$ clickhouse-local --structure "table_structure" --input-format "format_of_incoming_data" \
--query "query"
```
Arguments:
- `-S`, `--structure` — table structure for input data.
- `--input-format` — input format, `TSV` by default.
- `-f`, `--file` — path to data, `stdin` by default.
- `-q`, `--query` — queries to execute with `;` as delimeter. You must specify either `query` or `queries-file` option.
- `--queries-file` - file path with queries to execute. You must specify either `query` or `queries-file` option.
- `-N`, `--table` — table name where to put output data, `table` by default.
- `--format`, `--output-format` — output format, `TSV` by default.
- `-d`, `--database` — default database, `_local` by default.
- `--stacktrace` — whether to dump debug output in case of exception.
- `--echo` — print query before execution.
- `--verbose` — more details on query execution.
- `--logger.console` — Log to console.
- `--logger.log` — Log file name.
- `--logger.level` — Log level.
- `--ignore-error` — do not stop processing if a query failed.
- `-c`, `--config-file` — path to configuration file in same format as for ClickHouse server, by default the configuration empty.
- `--no-system-tables` — do not attach system tables.
- `--help` — arguments references for `clickhouse-local`.
- `-V`, `--version` — print version information and exit.
Also there are arguments for each ClickHouse configuration variable which are more commonly used instead of `--config-file`.
## Examples {#examples}
``` bash
$ echo -e "1,2\n3,4" | clickhouse-local --structure "a Int64, b Int64" \
--input-format "CSV" --query "SELECT * FROM table"
Read 2 rows, 32.00 B in 0.000 sec., 5182 rows/sec., 80.97 KiB/sec.
1 2
3 4
```
Previous example is the same as:
``` bash
$ echo -e "1,2\n3,4" | clickhouse-local --query "
CREATE TABLE table (a Int64, b Int64) ENGINE = File(CSV, stdin);
SELECT a, b FROM table;
DROP TABLE table"
Read 2 rows, 32.00 B in 0.000 sec., 4987 rows/sec., 77.93 KiB/sec.
1 2
3 4
```
You don't have to use `stdin` or `--file` argument, and can open any number of files using the [`file` table function](../../sql-reference/table-functions/file.md):
``` bash
$ echo 1 | tee 1.tsv
1
$ echo 2 | tee 2.tsv
2
$ clickhouse-local --query "
select * from file('1.tsv', TSV, 'a int') t1
cross join file('2.tsv', TSV, 'b int') t2"
1 2
```
Now lets output memory user for each Unix user:
Query:
``` bash
$ ps aux | tail -n +2 | awk '{ printf("%s\t%s\n", $1, $4) }' \
| clickhouse-local --structure "user String, mem Float64" \
--query "SELECT user, round(sum(mem), 2) as memTotal
FROM table GROUP BY user ORDER BY memTotal DESC FORMAT Pretty"
```
Result:
``` text
Read 186 rows, 4.15 KiB in 0.035 sec., 5302 rows/sec., 118.34 KiB/sec.
┏━━━━━━━━━━┳━━━━━━━━━━┓
┃ user ┃ memTotal ┃
┡━━━━━━━━━━╇━━━━━━━━━━┩
│ bayonet │ 113.5 │
├──────────┼──────────┤
│ root │ 8.8 │
├──────────┼──────────┤
...
```
[Original article](https://clickhouse.com/docs/en/operations/utils/clickhouse-local/) <!--hide-->
## Related Content
- [Getting Data Into ClickHouse - Part 1](https://clickhouse.com/blog/getting-data-into-clickhouse-part-1)
- [Exploring massive, real-world data sets: 100+ Years of Weather Records in ClickHouse](https://clickhouse.com/blog/real-world-data-noaa-climate-data)