Fixes #7640, add [Debug] log_sql_queries INI option to control whether SQL queries are logged.

config/global.ini.php

@@ -119,6 +119,9 @@ tracker_always_new_visitor = 0
 ; Allow automatic upgrades to Beta or RC releases
 allow_upgrades_to_beta = 0
 
+; if set to 1, all SQL queries will be logged using the DEBUG log level
+log_sql_queries = 0
+
 [DebugTests]
 ; When set to 1, standalone plugins (those with their own git repositories)
 ; will be loaded when executing tests.

core/Db.php

@@ -717,7 +717,9 @@ class Db
 
     private static function logSql($functionName, $sql, $parameters = array())
     {
-        if (self::$logQueries === false) {
+        if (self::$logQueries === false
+            || @Config::getInstance()->Debug['log_sql_queries'] != 1
+        ) {
             return;
         }