Do not report ERROR when sample rate equals 100

src/sql/engine/expr/ob_expr_concat.cpp

@@ -497,12 +497,5 @@ int ObExprConcat::eval_concat(const ObExpr &expr, ObEvalCtx &ctx, ObDatum &expr_
   return ret;
 }
 
-DEF_SET_LOCAL_SESSION_VARS(ObExprConcat, raw_expr) {
-  int ret = OB_SUCCESS;
-  SET_LOCAL_SYSVAR_CAPACITY(1);
-  EXPR_ADD_LOCAL_SYSVAR(share::SYS_VAR_COLLATION_CONNECTION);
-  return ret;
-}
-
 }
 }