Port of PR #4822 to v3.0

lib/MySQL_Logger.cpp

@@ -1463,7 +1463,9 @@ int MySQL_Logger::processEvents(SQLite3DB * statsdb , SQLite3DB * statsdb_disk)
 			int rows_to_keep = maxInMemorySize - events.size();
 			if (current_rows > rows_to_keep) {
 				int rows_to_delete = (current_rows - rows_to_keep);
-				string delete_stmt = "DELETE FROM stats_mysql_query_events ORDER BY id LIMIT " + to_string(rows_to_delete);
+				string query = "SELECT MAX(id) FROM (SELECT id FROM stats_mysql_query_events ORDER BY id LIMIT " + to_string(rows_to_delete) + ")";
+				int maxIdToDelete = statsdb->return_one_int(query.c_str());
+				string delete_stmt = "DELETE FROM stats_mysql_query_events WHERE id <= " + to_string(maxIdToDelete);
 				statsdb->execute(delete_stmt.c_str());
 			}
 		}

lib/ProxySQL_Admin_Stats.cpp

@@ -594,7 +594,7 @@ void ProxySQL_Admin::stats___mysql_global() {
 
 
 	if (GloMyLogger != nullptr) {
-		const string prefix = "MySQL_Logger-";
+		const string prefix = "MySQL_Logger_";
 		std::unordered_map<std::string, unsigned long long> metrics = GloMyLogger->getAllMetrics();
 		for (std::unordered_map<std::string, unsigned long long>::iterator it = metrics.begin(); it != metrics.end(); it++) {
 			unsigned int l = strlen(a) + prefix.length() + it->first.length() + 32;