Merge pull request #6963 from nicelulu/issue_6616

optimize limit 1,0 and test.

dbms/src/Interpreters/InterpreterSelectQuery.cpp

@@ -790,7 +790,7 @@ static std::pair<UInt64, UInt64> getLimitLengthAndOffset(const ASTSelectQuery &
     if (query.limitLength())
     {
         length = getLimitUIntValue(query.limitLength(), context);
-        if (query.limitOffset())
+        if (query.limitOffset() && length)
             offset = getLimitUIntValue(query.limitOffset(), context);
     }
 

dbms/tests/queries/0_stateless/01012_select_limit_x_0.sql

+SELECT count() FROM system.numbers LIMIT 1, 0;