[CBRD-24682] Fix error handling problem caused by CBRD-24585 (CUBRID#…

…4147)

http://jira.cubrid.org/browse/CBRD-24682

- Set error contexts in prepare() and execute() functions correctly.
- In execute(), setting error should be done again after ER_QPROC_INVALID_XASLNODE is handled.
- Remove redundant setting error context after db_execute_and_keep_statement ().

src/method/method_callback.cpp

@@ -126,11 +126,16 @@ namespace cubmethod
 	  }
 	else
 	  {
-	    if (handler->prepare (sql, flag) == NO_ERROR)
+	    int error = handler->prepare (sql, flag);
+	    if (error == NO_ERROR)
 	      {
 		// add to statement handler cache
 		m_sql_handler_map.emplace (sql, handler->get_id ());
 	      }
+	    else
+	      {
+		m_error_ctx.set_error (db_error_code (), db_error_string (1), __FILE__, __LINE__);
+	      }
 	  }
       }
 
@@ -161,8 +166,8 @@ namespace cubmethod
     if (handler == nullptr)
       {
 	// TODO: proper error code
-	m_error_ctx.set_error (METHOD_CALLBACK_ER_NO_MORE_MEMORY, NULL, __FILE__, __LINE__);
-	return ER_FAILED;
+	m_error_ctx.set_error (METHOD_CALLBACK_ER_INTERNAL, NULL, __FILE__, __LINE__);
+	assert (false); // the error should have been handled in prepare function
       }
     else
       {
@@ -180,14 +185,22 @@ namespace cubmethod
 	else
 	  {
 	    /* XASL cache is not found */
-	    m_error_ctx.clear ();
-	    handler->prepare_retry ();
-	    handler->execute (request);
+	    if (error == ER_QPROC_INVALID_XASLNODE)
+	      {
+		m_error_ctx.clear ();
+		handler->prepare_retry ();
+		error = handler->execute (request);
+	      }
+
+	    if (error != NO_ERROR)
+	      {
+		m_error_ctx.set_error (db_error_code (), db_error_string (1), __FILE__, __LINE__);
+	      }
 	  }
-      }
 
-    /* DDL audit */
-    logddl_write_end ();
+	/* DDL audit */
+	logddl_write_end ();
+      }
 
     if (m_error_ctx.has_error())
       {

src/method/method_query_handler.cpp

@@ -673,7 +673,6 @@ namespace cubmethod
     int n = db_execute_and_keep_statement (m_session, stmt_id, &result);
     if (n < 0)
       {
-	m_error_ctx.set_error (n, NULL, __FILE__, __LINE__);
 	return ER_FAILED;
       }
     else if (result != NULL)