如果在Oracle中不存在记录,如何插入记录？

如果记录在Oracle中不存在,如何插入记录？这是我想要做的：

IF NOT EXISTS (SELECT * FROM AROH_FAA_AIRPORT WHERE AIRPORT_ABBREVIATION = '0D7') 
BEGIN 
  insert into AROH_FAA_AIRPORT 
  (FAA_AIRPORT_OID,CITY,FAA_LISTED_AIRPORT_NAME,AIRPORT_ABBREVIATION) 
  values(AROH_FAA_AIRPORT_SEQ.nextval,'ADA','0D7') 
END

解决方法

insert into AROH_FAA_AIRPORT 
   (FAA_AIRPORT_OID,AIRPORT_ABBREVIATION) 
select AROH_FAA_AIRPORT_SEQ.nextval,'0D7') 
from dual 
where not exists (select 42
                  from AROH_FAA_AIRPORT 
                  WHERE AIRPORT_ABBREVIATION = '0D7');

或者,您可以使用MERGE语句：

merge into AROH_FAA_AIRPORT a
using (
    select 'ADA' city,'ADA' as faa_listed_airport_name,'0D7' as as airport_abbreviation 
    from dual 
) t ON (t.city = a.city)
when not matched then 
  insert 
     (FAA_AIRPORT_OID,AIRPORT_ABBREVIATION)
  values 
     (AROH_FAA_AIRPORT_SEQ.nextval,t.city,t.faa_listed_airport_name,t.airport_abbreviation);