一些有用的oracle sql语句

sql 查表空间语句:

 

SELECT UPPER(F.TABLESPACE_NAME) "表空间名",
       D.TOT_GROOTTE_MB "表空间大小(M)",
       D.TOT_GROOTTE_MB - F.TOTAL_BYTES "已使用空间(M)",
       TO_CHAR(ROUND((D.TOT_GROOTTE_MB - F.TOTAL_BYTES) / D.TOT_GROOTTE_MB * 100,
                     2),
               '990.99') "使用比",
       F.TOTAL_BYTES "空闲空间(M)",
       F.MAX_BYTES "最大块(M)"
FROM (SELECT TABLESPACE_NAME,
               ROUND(SUM(BYTES) / (1024 * 1024), 2) TOTAL_BYTES,
               ROUND(MAX(BYTES) / (1024 * 1024), 2) MAX_BYTES
          FROM SYS.DBA_FREE_SPACE
         GROUP BY TABLESPACE_NAME) F,
       (SELECT DD.TABLESPACE_NAME,
               ROUND(SUM(DD.BYTES) / (1024 * 1024), 2) TOT_GROOTTE_MB
          FROM SYS.DBA_DATA_FILES DD
         GROUP BY DD.TABLESPACE_NAME) D
WHERE D.TABLESPACE_NAME = F.TABLESPACE_NAME
ORDER BY 4 DESC

 

查看系统时间语句：

select sysdate from dual;

 

查看oracle的版本:

select version FROM Product_component_version Where SUBSTR(PRODUCT,1,6)='Oracle'