Join before wheres

ifad · Nov 8, 2021 · c809830 · c809830
1 parent 5725762
commit c809830
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Showing 2 changed files with 17 additions and 5 deletions.
diff --git a/lib/chrono_model/patches/relation.rb b/lib/chrono_model/patches/relation.rb
@@ -37,7 +37,13 @@ def chrono_join_history(join)
         #
         return if join.left.respond_to?(:as_of_time)
 
-        model = ChronoModel.history_models[join.left.table_name]
+        model =
+          if (join.left.respond_to?(:table_name))
+            ChronoModel.history_models[join.left.table_name]
+          else
+            ChronoModel.history_models[join.left]
+          end
+
         return unless model
 
         join.left = ChronoModel::Patches::JoinNode.new(

diff --git a/lib/chrono_model/time_machine/timeline.rb b/lib/chrono_model/time_machine/timeline.rb
@@ -23,7 +23,15 @@ def timeline(record = nil, options = {})
           select("DISTINCT UNNEST(ARRAY[#{fields.join(',')}]) AS ts")
 
         if assocs.present?
-          relation = relation.joins(*assocs.map(&:name))
+          assocs.each do |ass|
+            # `join` first, then use `where`s
+            relation =
+              if ass.belongs_to?
+                relation.joins("LEFT JOIN #{ass.table_name} ON #{ass.table_name}.id = #{table_name}.#{ass.foreign_key}")
+              else
+                relation.joins("LEFT JOIN #{ass.table_name} ON #{ass.table_name}.#{ass.foreign_key} = #{table_name}.id")
+              end
+          end
         end
 
         relation = relation.
@@ -32,7 +40,7 @@ def timeline(record = nil, options = {})
         relation = relation.from(%["public".#{quoted_table_name}]) unless self.chrono?
         relation = relation.where(id: rid) if rid
 
-        sql = "SELECT ts FROM ( #{relation.to_sql} ) foo WHERE ts IS NOT NULL"
+        sql = "SELECT ts FROM ( #{relation.to_sql} ) AS foo WHERE ts IS NOT NULL"
 
         if options.key?(:before)
           sql << " AND ts < '#{Conversions.time_to_utc_string(options[:before])}'"
@@ -50,8 +58,6 @@ def timeline(record = nil, options = {})
 
         sql << " LIMIT #{options[:limit].to_i}" if options.key?(:limit)
 
-        sql.gsub! 'INNER JOIN', 'LEFT OUTER JOIN'
-
         connection.on_schema(Adapter::HISTORY_SCHEMA) do
           connection.select_values(sql, "#{self.name} periods").map! do |ts|
             Conversions.string_to_utc_time ts