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aa86129e19
Hash joins can support semijoin with the LHS input on the right, using the existing logic for inner join, combined with the assurance that only the first match for each inner tuple is considered, which can be achieved by leveraging the HEAP_TUPLE_HAS_MATCH flag. This can be very useful in some cases since we may now have the option to hash the smaller table instead of the larger. Merge join could likely support "Right Semi Join" too. However, the benefit of swapping inputs tends to be small here, so we do not address that in this patch. Note that this patch also modifies a test query in join.sql to ensure it continues testing as intended. With this patch the original query would result in a right-semi-join rather than semi-join, compromising its original purpose of testing the fix for neqjoinsel's behavior for semi-joins. Author: Richard Guo Reviewed-by: wenhui qiu, Alena Rybakina, Japin Li Discussion: https://postgr.es/m/CAMbWs4_X1mN=ic+SxcyymUqFx9bB8pqSLTGJ-F=MHy4PW3eRXw@mail.gmail.com |
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| .. | ||
| expected | ||
| sql | ||
| .gitignore | ||
| connection.c | ||
| deparse.c | ||
| Makefile | ||
| meson.build | ||
| option.c | ||
| postgres_fdw--1.0--1.1.sql | ||
| postgres_fdw--1.0.sql | ||
| postgres_fdw.c | ||
| postgres_fdw.control | ||
| postgres_fdw.h | ||
| shippable.c | ||