Fix param-extraction

assets/javascripts/discourse/templates/admin/plugins-explorer.hbs

@@ -1,6 +1,6 @@
 <h3>Queries</h3>
 <div class="query-list">
-  {{combo-box valueAttribute="id" value=selectedQueryId nameProperty="listName" content=content castInteger="true"}}
+  {{combo-box valueAttribute="id" value=selectedQueryId nameProperty="listName" content=content castInteger="true" nameChanges="true"}}
   {{d-button action="showCreate" icon="plus" class="no-text"}}
   {{d-button action="importQuery" label="explorer.import.label" icon="upload"}}
 </div>

plugin.rb

@@ -47,10 +47,14 @@ after_initialize do
     #   (The first name is $0.)
     def self.extract_params(sql)
       names = []
-      new_sql = sql.gsub(/:([a-z_]+)/) do |_|
+      new_sql = sql.gsub(/(:?):([a-z_]+)/) do |_|
+        if $1 == ':' # skip casts
+          $&
+        else
           names << $1
           "$#{names.length - 1}"
         end
+      end
       {sql: new_sql, names: names}
     end