Oracle常用的查询语句

SELECT * from user_views where view_name='v$session'；
SELECT * FROM ALL_USERS where username like 'S%'；
select * from v$database；
select username,profile from dba_users;；
select * from dba_profiles where profile='DEFAULT'；
SELECT * from v$archive_dest；
select * from v$kccle;
select * from v$logfile；
select * from v$archive_dest；
select * from v$archive_dest_status；
select * from dba_tables T where owner='SYSTEM' AND TABLE_NAME LIKE 'FAM%'；
analyze table family compute statistics for table--表分析；
select * from user_tables where table_name='FAMILY'；
select * from v$parameter where name='db_block_size'；
select segment_name,bytes from user_segments；
select count(*) from all_tables；
select count(*) from dba_tables；
select * from dba_tables where tablespace_name='SYSTEM' and table_name='FAMILY'；
select segment_name,count(*),round(sum(bytes/1024/1024)，9） MB from user_segments group by segment_name order by MB desc；
select * from REPCAT$_DDL；
select * from user_segments wheRE segment_name='REPCAT$_DDL'；
select count(*) from user_tables；
select * from DBA_tables WHERE TABLE_NAME='SYSTEM'；

SELECT SUM(BYTES/1024/1024) FROM DBA_EXTENTS WHERE SEGMENT_NAME='FAMILY'；
SELECT SUM(BYTES/1024/1024) FROM DBA_DATA_FILES WHERE TABLESPACE_NAME='SYSTEM'；
SELECT SUM(BYTES/1024/1024) FROM DBA_FREE_SPACE WHERE TABLESPACE_NAME='SYSTEM'；
SELECT SEGMENT_NAME,sum(bytes/1024/1024) from user_segments group by segment_name having segment_name='FAMILY'；
SELECT SUM(BYTES/1024/1024) FROM DBA_EXTENTS WHERE SEGMENT_NAME='FAMILY'；
SELECT SUM(BYTES/1024/1024) FROM USER_SEGMENTS WHERE SEGMENT_NAME='FAMILY'；
SELECT 1-104.5625/810 FROM DUAL；
/*select a.tablespace_name,a.bytes/1024/1024 "sum MB",(a.bytes-b.bytes)/1024/1024 "used MB",b.bytes/1024/1024 "free MB",round(((a.bytes-b.bytes)/a.bytes)*100,2) "percent_used"
from
(select tablespace_name,sum(bytes) bytes from dba_data_files group by tablespace_name) a,
(select tablespace_name,sum(bytes) bytes,max(bytes) largest from dba_free_space group by tablespace_name) b
where a.tablespace_name=b.tablespace_name
order by ((a.bytes-b.bytes)/a.bytes) desc
--表空间*/
select SUM(BYTES/1024/1024) from SYS.DBA_FREE_SPACE t WHERE TABLESPACE_NAME='SYSTEM'；
SELECT TABLESPACE_NAME,SUM(BYTES/1024/1024) MB FROM DBA_DATA_FILES GROUP BY TABLESPACE_NAME；
SELECT SUM(BYTES/1024/1024) MB FROM DBA_DATA_FILES WHERE TABLESPACE_NAME='SYSTEM'；
select * from SYS.DBA_FREE_SPACE t；
SELECT * FROM DBA_EXTENTS WHERE SEGMENT_NAME='FAMILY'；
SELECT SUM(BYTES/1024/1024) MB FROM DBA_EXTENTS WHERE SEGMENT_NAME='FAMILY' ；--表的大小；
SELECT BYTES/1024/1024 FROM DBA_SEGMENTS WHERE SEGMENT_NAME='FAMILY'；--表的大小
select * from v$parameter where name='db_block_size'；--块的大小
select blocks*8/1024 from user_tables where table_name='FAMILY'；--表的大小

select sql_text,first_load_time from v$sql order by first_load_time desc；
commit；
select * from family；
delete from family where name='zXq'；
alter system switch logfile；--重做日志切换,切换后归档日志也会切换
select * from v$logfile； --重做日志
select * from v$archive_dest；--归档日志-
select * from v$parameter where name='db_recovery_file_dest_size'； --归档日志总大小-
select * from v$parameter where name like '%retention_target'；
select * from v$parameter where name='db_recovery_file_dest'；

select * from v$flashback_database_log；
select flashback_on from v$database；--查看数据库闪回功能有没有打开
select * from v$version;--数据库版本
select * from v$parameter where name like '%retention_target'；
select value/1024/1024/1024 AS "LOG/GB" from v$parameter where name='db_recovery_file_dest_size'--3.76171875；
select * from v$parameter where name='db_recovery_file_dest'；
select to_char(sysdate,'yyyy-mm-dd hh24:mi:ss') from dual;；
select * from user_recyclebin;--回收站
select * from v$parameter where name='background_dump_dest'；--警告文件和系统跟踪文件位置
select * from v$parameter where name='user_dump_dest'；--用户跟踪文件位置