29 lines
618 B
Markdown
29 lines
618 B
Markdown
# Aggregation functions
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`ormar` currently supports 2 aggregation functions:
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* `count() -> int`
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* `exists() -> bool`
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## count
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`count() -> int`
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Returns number of rows matching the given criteria (i.e. applied with `filter` and `exclude`)
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```python
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# returns count of rows in db for Books model
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no_of_books = await Book.objects.count()
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```
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## exists
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`exists() -> bool`
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Returns a bool value to confirm if there are rows matching the given criteria (applied with `filter` and `exclude`)
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```python
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# returns a boolean value if given row exists
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has_sample = await Book.objects.filter(title='Sample').exists()
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```
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