SY項目開發隨記

編譯器字符集：-Dfile.encoding=UTF-8

編譯器(Eclipse)內存： -Xms256m -Xmx512m -XX:PermSize=256m -XX:MaxPermSize=512m

--查詢空格
select t.*, t.rowid from HR_EDUCATION t  where regexp_like(t.start_date, '( )+');

merge into 目標表 a
using 源表 b
on(a.條件字段1=b.條件字段1 and a.條件字段2=b.條件字段2 ……)  
when matched then update set a.更新字段=b.字段
when  not macthed then insert into a(字段1,字段2……)values(值1,值2……)
 

數據庫備份批處理：

set fileName=%date:~0,4%%date:~5,2%%date:~8,2%%time:~0,2%%time:~3,2%%time:~6,2%
set fileName=HR%fileName: =0%.dmp
echo %fileName%
exp admin/admin1234@ORCL file=E:\backup\database\%fileName% log=E:\backup\database\exp.log owner=(admin)
exit

Oracle數據庫日誌查詢：

select t.SQL_TEXT, t.FIRST_LOAD_TIME
from v$sqlarea t
where t.FIRST_LOAD_TIME like '2018-11-08%'
order by t.FIRST_LOAD_TIME desc