mirror of https://github.com/zulip/zulip.git
31 lines
798 B
Python
31 lines
798 B
Python
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from typing import List, TypeVar
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from django.db import models
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from django_stubs_ext import ValuesQuerySet
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ModelT = TypeVar("ModelT", bound=models.Model)
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RowT = TypeVar("RowT")
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def query_for_ids(
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query: ValuesQuerySet[ModelT, RowT],
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user_ids: List[int],
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field: str,
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) -> ValuesQuerySet[ModelT, RowT]:
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"""
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This function optimizes searches of the form
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`user_profile_id in (1, 2, 3, 4)` by quickly
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building the where clauses. Profiling shows significant
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speedups over the normal Django-based approach.
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Use this very carefully! Also, the caller should
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guard against empty lists of user_ids.
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"""
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assert user_ids
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clause = f"{field} IN %s"
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query = query.extra(
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where=[clause],
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params=(tuple(user_ids),),
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)
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return query
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