fix: Avoid joining tables to fix the distinct value query (#7965)

DISTINCT query with custom attributes return an error. To avoid the error, this PR refactors the query to include tags only when it is required.

Fixes #7931
Fixes #7836

Co-authored-by: Sojan Jose <sojan@pepalo.com>

app/services/contacts/filter_service.rb

@@ -35,7 +35,7 @@ class Contacts::FilterService < FilterService
       " (contacts.#{attribute_key})::#{current_filter['data_type']} #{filter_operator_value}#{current_filter['data_type']} #{query_operator} "
     when 'standard'
       if attribute_key == 'labels'
-        " tags.id #{filter_operator_value} #{query_operator} "
+        tag_filter_query('Contact', 'contacts', query_hash, current_index)
       else
         " LOWER(contacts.#{attribute_key}) #{filter_operator_value} #{query_operator} "
       end
@@ -54,7 +54,7 @@ class Contacts::FilterService < FilterService
   end
 
   def base_relation
-    Current.account.contacts.distinct(:id).left_outer_joins(:labels)
+    Current.account.contacts
   end
 
   private

app/services/conversations/filter_service.rb

@@ -46,7 +46,7 @@ class Conversations::FilterService < FilterService
       " (conversations.#{attribute_key})::#{current_filter['data_type']} #{filter_operator_value}#{current_filter['data_type']} #{query_operator} "
     when 'standard'
       if attribute_key == 'labels'
-        " tags.name #{filter_operator_value} #{query_operator} "
+        tag_filter_query('Conversation', 'conversations', query_hash, current_index)
       else
         " conversations.#{attribute_key} #{filter_operator_value} #{query_operator} "
       end
@@ -54,7 +54,9 @@ class Conversations::FilterService < FilterService
   end
 
   def base_relation
-    @account.conversations.left_outer_joins(:labels)
+    @account.conversations.includes(
+      :taggings, :inbox, { assignee: { avatar_attachment: [:blob] } }, { contact: { avatar_attachment: [:blob] } }, :team, :messages, :contact_inbox
+    )
   end
 
   def current_page
@@ -62,10 +64,6 @@ class Conversations::FilterService < FilterService
   end
 
   def conversations
-    @conversations = @conversations.includes(
-      :taggings, :inbox, { assignee: { avatar_attachment: [:blob] } }, { contact: { avatar_attachment: [:blob] } }, :team, :messages, :contact_inbox
-    )
-
     @conversations.latest.page(current_page)
   end
 end

app/services/filter_service.rb

@@ -106,6 +106,27 @@ class FilterService
     ]
   end
 
+  def tag_filter_query(model_name, table_name, query_hash, current_index)
+    query_operator = query_hash[:query_operator]
+    @filter_values["value_#{current_index}"] = filter_values(query_hash)
+
+    tag_model_relation_query =
+      "SELECT * FROM taggings WHERE taggings.taggable_id = #{table_name}.id AND taggings.taggable_type = '#{model_name}'"
+    tag_query =
+      "AND taggings.tag_id IN (SELECT tags.id FROM tags WHERE tags.name IN (:value_#{current_index}))"
+
+    case query_hash[:filter_operator]
+    when 'equal_to'
+      "EXISTS (#{tag_model_relation_query} #{tag_query}) #{query_operator}"
+    when 'not_equal_to'
+      "NOT EXISTS (#{tag_model_relation_query} #{tag_query}) #{query_operator}"
+    when 'is_present'
+      "EXISTS (#{tag_model_relation_query}) #{query_operator}"
+    when 'is_not_present'
+      "NOT EXISTS (#{tag_model_relation_query}) #{query_operator}"
+    end
+  end
+
   def custom_attribute_query(query_hash, custom_attribute_type, current_index)
     @attribute_key = query_hash[:attribute_key]
     @custom_attribute_type = custom_attribute_type