How it difference between DBMS_STATS.GATHER_SCHEMA_STATS and DBMS_STATS.GATHER_TABLE_STATS?

    Hi,

I trying to use DBMS_STATS to collect statistic on DB 9.2.0.8, I have existing statistic on DB by using "ANALYZE" command but the information not show in last_analyzed column in DBA_TABLES.

some statement has problem when I use  DBMS_STATS.GATHER_SCHEMA_STATS('USERNAME',estimate_percent=>20,cascade=>true,degree=>2,method_opt=>'for all columns size 1');

but for gather by table it work fine (DBMS_STATS.GATHER_TABLE_STATS) I used only some table in schema.

Could you please explain how difference?

Regards,

Nim.