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@@ -894,27 +894,16 @@ class Query:
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def join(self, join, reuse=None):
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"""
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- Return an alias for the join in 'connection', either reusing an
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- existing alias for that join or creating a new one. 'connection' is a
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- tuple (lhs, table, join_cols) where 'lhs' is either an existing
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- table alias or a table name. 'join_cols' is a tuple of tuples containing
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- columns to join on ((l_id1, r_id1), (l_id2, r_id2)). The join corresponds
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- to the SQL equivalent of::
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+ Return an alias for the 'join', either reusing an existing alias for
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+ that join or creating a new one. 'join' is either a
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+ sql.datastructures.BaseTable or Join.
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- lhs.l_id1 = table.r_id1 AND lhs.l_id2 = table.r_id2
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-
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- The 'reuse' parameter can be either None which means all joins
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- (matching the connection) are reusable, or it can be a set containing
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- the aliases that can be reused.
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+ The 'reuse' parameter can be either None which means all joins are
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+ reusable, or it can be a set containing the aliases that can be reused.
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A join is always created as LOUTER if the lhs alias is LOUTER to make
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- sure we do not generate chains like t1 LOUTER t2 INNER t3. All new
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- joins are created as LOUTER if nullable is True.
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-
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- If 'nullable' is True, the join can potentially involve NULL values and
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- is a candidate for promotion (to "left outer") when combining querysets.
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-
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- The 'join_field' is the field we are joining along (if any).
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+ sure chains like t1 LOUTER t2 INNER t3 aren't generated. All new
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+ joins are created as LOUTER if the join is nullable.
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"""
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reuse = [a for a, j in self.alias_map.items()
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if (reuse is None or a in reuse) and j == join]
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