coalesce がマジ便利
select coalesce(null,1,null,2) from dual
↓
1
select coalesce(null,null,null,2) from dual
↓
2
select coalesce(null,null,null,null) from dual
↓
null
でもスペルが覚えられない
select coalesce(null,1,null,2) from dual
↓
1
select coalesce(null,null,null,2) from dual
↓
2
select coalesce(null,null,null,null) from dual
↓
null
でもスペルが覚えられない