mirror of
https://github.com/ClickHouse/ClickHouse.git
synced 2024-12-14 18:32:29 +00:00
40 lines
2.5 KiB
Markdown
40 lines
2.5 KiB
Markdown
---
|
||
slug: /en/operations/system-tables/functions
|
||
---
|
||
# functions
|
||
|
||
Contains information about normal and aggregate functions.
|
||
|
||
Columns:
|
||
|
||
- `name` ([String](../../sql-reference/data-types/string.md)) – The name of the function.
|
||
- `is_aggregate` ([UInt8](../../sql-reference/data-types/int-uint.md)) — Whether the function is an aggregate function.
|
||
- `case_insensitive`, ([UInt8](../../sql-reference/data-types/int-uint.md)) - Whether the function name can be used case-insensitively.
|
||
- `alias_to`, ([String](../../sql-reference/data-types/string.md)) - The original function name, if the function name is an alias.
|
||
- `create_query`, ([String](../../sql-reference/data-types/enum.md)) - Unused.
|
||
- `origin`, ([Enum8](../../sql-reference/data-types/string.md)) - Unused.
|
||
- `description`, ([String](../../sql-reference/data-types/string.md)) - A high-level description what the function does.
|
||
- `syntax`, ([String](../../sql-reference/data-types/string.md)) - Signature of the function.
|
||
- `arguments`, ([String](../../sql-reference/data-types/string.md)) - What arguments does the function take.
|
||
- `returned_value`, ([String](../../sql-reference/data-types/string.md)) - What does the function return.
|
||
- `examples`, ([String](../../sql-reference/data-types/string.md)) - Example usage of the function.
|
||
- `categories`, ([String](../../sql-reference/data-types/string.md)) - The category of the function.
|
||
|
||
**Example**
|
||
|
||
```sql
|
||
SELECT name, is_aggregate, is_deterministic, case_insensitive, alias_to FROM system.functions LIMIT 5;
|
||
```
|
||
|
||
```text
|
||
┌─name─────────────────────┬─is_aggregate─┬─is_deterministic─┬─case_insensitive─┬─alias_to─┐
|
||
│ BLAKE3 │ 0 │ 1 │ 0 │ │
|
||
│ sipHash128Reference │ 0 │ 1 │ 0 │ │
|
||
│ mapExtractKeyLike │ 0 │ 1 │ 0 │ │
|
||
│ sipHash128ReferenceKeyed │ 0 │ 1 │ 0 │ │
|
||
│ mapPartialSort │ 0 │ 1 │ 0 │ │
|
||
└──────────────────────────┴──────────────┴──────────────────┴──────────────────┴──────────┘
|
||
|
||
5 rows in set. Elapsed: 0.002 sec.
|
||
```
|