Files
Nominatim/nominatim/api/search/db_search_lookups.py
2023-12-07 09:32:02 +01:00

115 lines
4.6 KiB
Python

# SPDX-License-Identifier: GPL-3.0-or-later
#
# This file is part of Nominatim. (https://nominatim.org)
#
# Copyright (C) 2023 by the Nominatim developer community.
# For a full list of authors see the git log.
"""
Implementation of lookup functions for the search_name table.
"""
from typing import List, Any
import sqlalchemy as sa
from sqlalchemy.ext.compiler import compiles
from nominatim.typing import SaFromClause
from nominatim.db.sqlalchemy_types import IntArray
# pylint: disable=consider-using-f-string
LookupType = sa.sql.expression.FunctionElement[Any]
class LookupAll(LookupType):
""" Find all entries in search_name table that contain all of
a given list of tokens using an index for the search.
"""
inherit_cache = True
def __init__(self, table: SaFromClause, column: str, tokens: List[int]) -> None:
super().__init__(table.c.place_id, getattr(table.c, column), column,
sa.type_coerce(tokens, IntArray))
@compiles(LookupAll) # type: ignore[no-untyped-call, misc]
def _default_lookup_all(element: LookupAll,
compiler: 'sa.Compiled', **kw: Any) -> str:
_, col, _, tokens = list(element.clauses)
return "(%s @> %s)" % (compiler.process(col, **kw),
compiler.process(tokens, **kw))
@compiles(LookupAll, 'sqlite') # type: ignore[no-untyped-call, misc]
def _sqlite_lookup_all(element: LookupAll,
compiler: 'sa.Compiled', **kw: Any) -> str:
place, col, colname, tokens = list(element.clauses)
return "(%s IN (SELECT CAST(value as bigint) FROM"\
" (SELECT array_intersect_fuzzy(places) as p FROM"\
" (SELECT places FROM reverse_search_name"\
" WHERE word IN (SELECT value FROM json_each('[' || %s || ']'))"\
" AND column = %s"\
" ORDER BY length(places)) as x) as u,"\
" json_each('[' || u.p || ']'))"\
" AND array_contains(%s, %s))"\
% (compiler.process(place, **kw),
compiler.process(tokens, **kw),
compiler.process(colname, **kw),
compiler.process(col, **kw),
compiler.process(tokens, **kw)
)
class LookupAny(LookupType):
""" Find all entries that contain at least one of the given tokens.
Use an index for the search.
"""
inherit_cache = True
def __init__(self, table: SaFromClause, column: str, tokens: List[int]) -> None:
super().__init__(table.c.place_id, getattr(table.c, column), column,
sa.type_coerce(tokens, IntArray))
@compiles(LookupAny) # type: ignore[no-untyped-call, misc]
def _default_lookup_any(element: LookupAny,
compiler: 'sa.Compiled', **kw: Any) -> str:
_, col, _, tokens = list(element.clauses)
return "(%s && %s)" % (compiler.process(col, **kw),
compiler.process(tokens, **kw))
@compiles(LookupAny, 'sqlite') # type: ignore[no-untyped-call, misc]
def _sqlite_lookup_any(element: LookupAny,
compiler: 'sa.Compiled', **kw: Any) -> str:
place, _, colname, tokens = list(element.clauses)
return "%s IN (SELECT CAST(value as bigint) FROM"\
" (SELECT array_union(places) as p FROM reverse_search_name"\
" WHERE word IN (SELECT value FROM json_each('[' || %s || ']'))"\
" AND column = %s) as u,"\
" json_each('[' || u.p || ']'))" % (compiler.process(place, **kw),
compiler.process(tokens, **kw),
compiler.process(colname, **kw))
class Restrict(LookupType):
""" Find all entries that contain all of the given tokens.
Do not use an index for the search.
"""
inherit_cache = True
def __init__(self, table: SaFromClause, column: str, tokens: List[int]) -> None:
super().__init__(getattr(table.c, column),
sa.type_coerce(tokens, IntArray))
@compiles(Restrict) # type: ignore[no-untyped-call, misc]
def _default_restrict(element: Restrict,
compiler: 'sa.Compiled', **kw: Any) -> str:
arg1, arg2 = list(element.clauses)
return "(coalesce(null, %s) @> %s)" % (compiler.process(arg1, **kw),
compiler.process(arg2, **kw))
@compiles(Restrict, 'sqlite') # type: ignore[no-untyped-call, misc]
def _sqlite_restrict(element: Restrict,
compiler: 'sa.Compiled', **kw: Any) -> str:
return "array_contains(%s)" % compiler.process(element.clauses, **kw)