`includes` uses SQL parsing when String joins are involved.

This is a partial revert of 22b3481ba2aa55fad1f9a5db94072312b345fb55.
The current implementation of `references_eager_loaded_tables?` needs to know
every table involved in the query. With the current API this is not possible
without SQL parsing.

While a2dab46cae35a06fd5c5500037177492a047c252 deprecated SQL parsing for `includes`.
It did not issue deprecation warnings when String joins are involved. This resulted
in a breaking change after the deprecated behavior was removed (22b3481ba2aa55fad1f9a5db94072312b345fb55).

We will need to rethink the usage of `includes`, `preload` and `eager_load` but for now,
this brings back the old *working* behavior.

1 files changed, 10 insertions, 1 deletions

diff --git a/activerecord/lib/active_record/relation.rb b/activerecord/lib/active_record/relation.rb
index fb213dc6f7..9eaba4a655 100644
--- a/activerecord/lib/active_record/relation.rb
+++ b/activerecord/lib/active_record/relation.rb
@@ -617,7 +617,9 @@ module ActiveRecord
 
     def references_eager_loaded_tables?
       joined_tables = arel.join_sources.map do |join|
-        unless join.is_a?(Arel::Nodes::StringJoin)
+        if join.is_a?(Arel::Nodes::StringJoin)
+          tables_in_string(join.left)
+        else
           [join.left.table_name, join.left.table_alias]
         end
       end
@@ -629,5 +631,12 @@ module ActiveRecord
 
       (references_values - joined_tables).any?
     end
+
+    def tables_in_string(string)
+      return [] if string.blank?
+      # always convert table names to downcase as in Oracle quoted table names are in uppercase
+      # ignore raw_sql_ that is used by Oracle adapter as alias for limit/offset subqueries
+      string.scan(/([a-zA-Z_][.\w]+).?\./).flatten.map{ |s| s.downcase }.uniq - ['raw_sql_']
+    end
   end
 end