autotrace explain plan 相關引數解釋

1、以sys執行$ORACLE_HOME/sqlplus/admin/plustrce.sql
2、在user使用者下執行$ORACLE_HOME/rdbms/admin/utlxplan.sql，用於建plan_table表，並Grant PLUSTRACE to user  

引數：
SET AUTOTRACE OFF ： No AUTOTRACE report is generated. This is the default.
SET AUTOTRACE ON EXPLAIN ： The AUTOTRACE report shows only the optimizer execution path.
SET AUTOTRACE ON STATISTICS ： The AUTOTRACE report shows only the SQL statement execution statistics.
SET AUTOTRACE ON ： The AUTOTRACE report includes both the optimizer execution path and the SQL statement execution statistics.
SET AUTOTRACE TRACEONLY ： Like SET AUTOTRACE ON, but suppresses the printing of the user's query output, if any.