![]() ![]() The coalesce function is one function that gets a data set and finds the first record that doesn’t contain a null in the column you indicate. The SQL language includes some functions that help you remove null values from your data sets. However, nulls can cause issues if you’re trying to add values or find real values in your tables. The null is not “nothing” in terms of programming, but the null value indicates that no real value is stored in the database table field. I tend to agree, are you still interested in submitting a PR that does a config assignment in SearchLookup.Most databases have the ability to store the “null” value. I am inclined to think that making my own lookup would be the safest thing to do for now, with the lookups provided also considering the issue of transferring the configuration. I plan on working on patch that exposes an Expression.nullable property that gets assigned on field reference resolution but that's not an easy thing to get right as you might suspect. The JOIN resolution logic knows about these things but it's not surfaced at the Expression introspection level right now so we can't even start deprecating the current behaviour if we wanted to. ![]() Right comment:6 provides another example of that. In such cases, the characteristics of the output column would need to be defined by identifying its role in the query, pretty much as you say. For instance, any query involving an outer join could produce null values for a "not null" column. I'm still getting familiar with the ORM, but I imagine that there could easily be cases where column values are null even if the table columns are declared not null. Right the main issue here is that SearchVector (just like Concat for example) has been coalescing nulls to empty strings forever so we can't just change it now without breaking backward compatibility. This then becomes an issue of knowing when this might be guaranteed. I wouldn't expect to_tsvector to treat an empty string and null in the same way - this being SQL after all - but the aim would be to avoid coalesce where null could never occur. That would make filter(column_search=SearchQuery('simple', config='simple')) result in the desired to_tsvector('simple', column) plainto_tsquery('simple', 'keyword').įWIW that's already something we do for the SearchVectorExact lookup. Lhs, lhs_params = super().process_lhs(qn, connection) Self.lhs = SearchVector(self.lhs, config=config) If not isinstance(_field, SearchVectorField): SearchQuery, SearchVector, SearchVectorExact, SearchVectorFieldĬlass PostgresSimpleLookup(FieldGetDbPrepValueMixin, Lookup): search import SearchVector, SearchVectorExact, SearchVectorField
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