Fix ORDER BY with named aggregates that expand to subqueries (#34)

* Fix ORDER BY subquery aliases with parser rewrite

* Fix ORDER BY alias inlining

* Avoid ORDER BY alias rewrites in subqueries

* Respect real alias table qualifiers

* Fix alias qualifier regression test

* Group alias qualifier regression explicitly

* Narrow alias qualifier regression

* Avoid alias binder ambiguity in regression

Author: nicosuave

include/yardstick_ffi.h

@@ -177,6 +177,13 @@ void yardstick_free_aggregate_list(YardstickAggregateCallList* list);
  */
 YardstickSelectInfo* yardstick_parse_select(const char* sql);
 
+/**
+ * Inline SELECT aliases inside complex ORDER BY expressions when they reference
+ * a SELECT alias whose expression contains a subquery. Returns NULL when no
+ * rewrite is needed or parsing fails.
+ */
+char* yardstick_inline_order_by_subquery_aliases(const char* sql);
+
 /**
  * Free a select info structure.
  */

src/yardstick_extension.cpp

@@ -63,6 +63,7 @@ extern "C" {
         char* (*replace_range)(const char*, uint32_t, uint32_t, const char*),
         char* (*apply_replacements)(const char*, const YardstickReplacement*, size_t),
         char* (*qualify_expression)(const char*, const char*),
+        char* (*inline_order_by_subquery_aliases)(const char*),
         void (*free_string)(char*),
         char* (*expand_aggregate_call)(const char*, const char*, const YardstickAtModifier*, size_t, const char*, const char*, const char*, const char* const*, size_t)
     );
@@ -635,6 +636,7 @@ static void LoadInternal(ExtensionLoader &loader) {
         yardstick_replace_range,
         yardstick_apply_replacements,
         yardstick_qualify_expression,
+        yardstick_inline_order_by_subquery_aliases,
         yardstick_free_string,
         yardstick_expand_aggregate_call
     );