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docs: remove outdated druidversion var from a page (#16570) 

Co-authored-by: asdf2014 <asdf2014@apache.org>
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317brian 2024-06-10 00:30:36 -07:00 committed by GitHub
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docs/querying/datasource.md
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@ -365,7 +365,7 @@ GROUP BY
Join datasources allow you to do a SQL-style join of two datasources. Stacking joins on top of each other allows Join datasources allow you to do a SQL-style join of two datasources. Stacking joins on top of each other allows
you to join arbitrarily many datasources. you to join arbitrarily many datasources.
In Druid {{DRUIDVERSION}}, joins in native queries are implemented with a broadcast hash-join algorithm. This means Joins in native queries are implemented with a broadcast hash-join algorithm. This means
that all datasources other than the leftmost "base" datasource must fit in memory. In native queries, the join condition that all datasources other than the leftmost "base" datasource must fit in memory. In native queries, the join condition
must be an equality. In SQL, any join condition is accepted, but only equalities of a certain form must be an equality. In SQL, any join condition is accepted, but only equalities of a certain form
(see [Joins in SQL](#joins-in-sql)) execute efficiently as part of a native join. For other kinds of conditions, planner will try (see [Joins in SQL](#joins-in-sql)) execute efficiently as part of a native join. For other kinds of conditions, planner will try
@ -431,7 +431,7 @@ and how to detect it.
3. One common reason for implicit subquery generation is if the types of the two halves of an equality do not match. 3. One common reason for implicit subquery generation is if the types of the two halves of an equality do not match.
For example, since lookup keys are always strings, the condition `druid.d JOIN lookup.l ON d.field = l.field` will For example, since lookup keys are always strings, the condition `druid.d JOIN lookup.l ON d.field = l.field` will
perform best if `d.field` is a string. perform best if `d.field` is a string.
4. As of Druid {{DRUIDVERSION}}, the join operator must evaluate the condition for each row. In the future, we expect 4. The join operator must evaluate the condition for each row. In the future, we expect
to implement both early and deferred condition evaluation, which we expect to improve performance considerably for to implement both early and deferred condition evaluation, which we expect to improve performance considerably for
common use cases. common use cases.
5. Currently, Druid does not support pushing down predicates (condition and filter) past a Join (i.e. into 5. Currently, Druid does not support pushing down predicates (condition and filter) past a Join (i.e. into