1Z0-032單項(xiàng)選擇題每日一練(2019.01.12)

Consider the following statement：  
SQL> EXECUTE DBMS_STATS.GATHER_SHEMA_STATS （- 
2> ownname => ‘OE’， - 
3> estimate_percent => DBMS_STATS.AUTO_SAMPLE_SIZE， - 
4> method opt => ‘for all columns size AUTO’）；  
What is the effect of ‘for all columns size AUTO’ of the METHOD_OPT option？（）

You received these error messages because the client cannot find the desired database：  
ORA-12198： TNS：could not path to destination 
ORA-12203： TNS：unable to connect to destination 
Which action would be appropriate in helping to resolve the errors？（）