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