if (varName.startsWith("@@") && !checkVar(x.getParent(), x.getName())) {
final WallTopStatementContext topStatementContext = WallVisitorUtils.getWallTopStatementContext();
if (topStatementContext != null
&& (topStatementContext.fromSysSchema() || topStatementContext.fromSysTable())) {
return false;
}
boolean isTop = WallVisitorUtils.isTopNoneFromSelect(this, x);
if (!isTop) {