Hello, On Mon, 2022-08-08 at 15:52 +0800, Wind wrote: > hi~ > I test "tablesample" feature on pg9.5 and found that tablesample > doesnt support to be applied to subquery. > for example this sql doesnt work on pg9.5: > ``` > create table t1( > c1 int, > c2 int > ); > select c2 from (select * from t1) as t2 tablesample system (50); > ``` > while i read sql2003 standard about tablesample and think it should > allow this usage according to standard. > is it a deviation to sql standard? Version 9.5 is not supported. The oldest supported version is 10, the current version is 14. Please read chapter 58 in the doco. HTH,
