nushell/docs/commands/where.md
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# where
This command filters the content of a table based on a condition passed as a parameter, which must be a boolean expression making use of any of the table columns. Other commands such as `ls` are capable of feeding `where` with their output through pipelines.
Where has two general forms:
- `where <column_name> <comparison> <value>`
- `where <column_name>`
## Where with comparison
In the first form, `where` is passed a column name that the filter will run against. Next, is the operator used to compare this column to its value. The following operators are supported:
- `<` (less than)
- `<=` (less than or equal)
- `>` (greater than)
- `>=` (greater than or equal)
- `!=` (not equal)
- `==` (equal)
Strings have two additional operators:
- `=~` (fuzzy match to allow)
- `!~` (fuzzy match to not allow)
Dates can also be compared using the duration types. For example, `where accessed > 2w` will check the date in accessed to see if it's greater than 2 weeks ago. Durations currently allow these abbreviations:
- `1s` (one second)
- `1m` (one minute)
- `1h` (one hour)
- `1d` (one day)
- `1w` (one week)
- `1M` (one month)
- `1y` (one year)
## Boolean check
Where with the form `| where readonly` is used to check boolean values. For example, the command `ls --full | where readonly` will list only those files that are readonly.
## Usage
```shell
> [input-command] | where [condition]
```
## Examples
```shell
> ls | where size > 4kb
━━━┯━━━━━━━━━━━━┯━━━━━━┯━━━━━━━━━┯━━━━━━━━━━━━━┯━━━━━━━━━━━━━┯━━━━━━━━━━━━━
# │ name │ type │ size │ created │ accessed │ modified
───┼────────────┼──────┼─────────┼─────────────┼─────────────┼─────────────
0 │ Cargo.lock │ File │ 87.2 KB │ 7 hours ago │ 7 hours ago │ 7 hours ago
1 │ README.md │ File │ 19.5 KB │ 7 hours ago │ 7 hours ago │ 7 hours ago
2 │ Cargo.toml │ File │ 4.7 KB │ 7 hours ago │ 7 hours ago │ 7 hours ago
━━━┷━━━━━━━━━━━━┷━━━━━━┷━━━━━━━━━┷━━━━━━━━━━━━━┷━━━━━━━━━━━━━┷━━━━━━━━━━━━━
```
```shell
> ps | where cpu > 0
━━━┯━━━━━━━┯━━━━━━━━━━━━━━━━━━━━━━━┯━━━━━━━━━━┯━━━━━━━━━━━━━━━━━━━
# │ pid │ name │ status │ cpu
───┼───────┼───────────────────────┼──────────┼───────────────────
01546 │ Xorg │ Sleeping │ 10.65405000000000
11769 │ gnome-shell │ Sleeping │ 5.271094000000000
22153 │ gnome-terminal-server │ Sleeping │ 5.193664000000000
313556 │ nu_plugin_ps │ Sleeping │ 40.70250000000000
━━━┷━━━━━━━┷━━━━━━━━━━━━━━━━━━━━━━━┷━━━━━━━━━━┷━━━━━━━━━━━━━━━━━━━
```
```shell
> ls | where accessed <= 1w
━━━┯━━━━━━━━━━━━━━━┯━━━━━━━━━━━┯━━━━━━━━━━┯━━━━━━━━━━━━┯━━━━━━━━━━━━
# │ name │ type │ size │ accessed │ modified
───┼───────────────┼───────────┼──────────┼────────────┼────────────
0 │ Cargo.toml │ File │ 4.7 KB │ 2 days ago │ 2 days ago
1 │ target │ Directory │ 4.1 KB │ 2 days ago │ 2 days ago
2 │ Makefile.toml │ File │ 449 B │ 4 days ago │ 4 days ago
3 │ README.md │ File │ 19.5 KB │ 2 days ago │ 2 days ago
4 │ Cargo.lock │ File │ 170.7 KB │ 2 days ago │ 2 days ago
5 │ crates │ Directory │ 4.1 KB │ 2 days ago │ 2 days ago
6 │ TODO.md │ File │ 1.3 KB │ 2 days ago │ 2 days ago
━━━┷━━━━━━━━━━━━━━━┷━━━━━━━━━━━┷━━━━━━━━━━┷━━━━━━━━━━━━┷━━━━━━━━━━━━
```
```shell
> ls | where name =~ "yml"
━━━━━━━━━━━━━┯━━━━━━┯━━━━━━━┯━━━━━━━━━━━━┯━━━━━━━━━━━━
name │ type │ size │ accessed │ modified
─────────────┼──────┼───────┼────────────┼────────────
.gitpod.yml │ File │ 780 B │ a week ago │ a week ago
━━━━━━━━━━━━━┷━━━━━━┷━━━━━━━┷━━━━━━━━━━━━┷━━━━━━━━━━━━
```