oracle数据库经典SQL查询
1、查看表空间的名称及大小
select t.tablespace_name, round(sum(bytes/(1024*1024)),0) ts_size
from dba_tablespaces t, dba_data_files d
where t.tablespace_name = d.tablespace_name
group by t.tablespace_name;
2、查看表空间物理文件的名称及大小
select tablespace_name, file_id, file_name,
round(bytes/(1024*1024),0) total_space
from dba_data_files
order by tablespace_name;
3、查看回滚段名称及大小
select segment_name, tablespace_name, r.status,
(initial_extent/1024) InitialExtent,(next_extent/1024) NextExtent,
max_extents, v.curext CurExtent
From dba_rollback_segs r, v$rollstat v
Where r.segment_id = v.usn(+)
order by segment_name ;
4、查看控制文件
select name from v$controlfile;
5、查看日志文件
select member from v$logfile;
6、查看表空间的使用情况
select sum(bytes)/(1024*1024) as free_space,tablespace_name
from dba_free_space
group by tablespace_name;
SELECT A.TABLESPACE_NAME,A.BYTES TOTAL,B.BYTES USED, C.BYTES FREE,
(B.BYTES*100)/A.BYTES "% USED",(C.BYTES*100)/A.BYTES "% FREE"
FROM SYS.SM$TS_AVAIL A,SYS.SM$TS_USED B,SYS.SM$TS_FREE C
WHERE A.TABLESPACE_NAME=B.TABLESPACE_NAME AND A.TABLESPACE_NAME=C.TABLESPACE_NAME;
7、查看数据库库对象
select owner, object_type, status, count(*) count# from all_objects group by owner, object_type, status;
8、查看数据库的版本
Select version FROM Product_component_version
Where SUBSTR(PRODUCT,1,6)='Oracle';
9、查看数据库的创建日期和归档方式
Select Created, Log_Mode, Log_Mode From V$Database;
10、捕捉运行很久的SQL
column username format a12
column opname format a16
column progress format a8
select username,sid,opname,
round(sofar*100 / totalwork,0) || '%' as progress,
time_remaining,sql_text
from v$session_longops , v$sql
where time_remaining <> 0
and sql_address = address
and sql_hash_value = hash_value
/
11。查看数据表的参数信息
SELECT partition_name, high_value, high_value_length, tablespace_name, pct_free, pct_used, ini_trans, max_trans, initial_extent, next_extent, min_extent, max_extent, pct_increase, FREELISTS, freelist_groups, LOGGING, BUFFER_POOL, num_rows, blocks, empty_blocks, avg_space, chain_cnt, avg_row_len, sample_size, last_analyzed FROM dba_tab_partitions --WHERE table_name = :tname AND table_owner = :townerORDER BY partition_position
12.查看还没提交的事务
select * from v$locked_object;
select * from v$transaction;
13。查找object为哪些进程所用
select p.spid,s.sid,s.serial# serial_num,s.username user_name,a.type object_type,s.osuser os_user_name,a.owner,a.object object_name,decode(sign(48 - command),1,to_char(command), 'Action Code #' || to_char(command) ) action,p.program oracle_process,s.terminal terminal,s.program program,s.status session_status from v$session s, v$access a, v$process p where s.paddr = p.addr and s.type = 'USER' and a.sid = s.sid and a.object='SUBSCRIBER_ATTR'order by s.username, s.osuser
14。回滚段查看
select rownum, sys.dba_rollback_segs.segment_name Name, v$rollstat.extents Extents, v$rollstat.rssize Size_in_Bytes, v$rollstat.xacts XActs, v$rollstat.gets Gets, v$rollstat.waits Waits, v$rollstat.writes Writes, sys.dba_rollback_segs.status status from v$rollstat, sys.dba_rollback_segs, v$rollname where v$rollname.name(+) = sys.dba_rollback_segs.segment_name and v$rollstat.usn (+) = v$rollname.usn order by rownum
15。耗资源的进程（top session）
select s.schemaname schema_name, decode(sign(48 - command), 1, to_char(command), 'Action Code #' || to_char(command) ) action, status session_status, s.osuser os_user_name, s.sid, p.spid , s.serial# serial_num, nvl(s.username, '[Oracle process]') user_name, s.terminal terminal, s.program program, st.value criteria_value from v$sesstat st, v$session s , v$process p where st.sid = s.sid and st.statistic# = to_number('38') and ('ALL' = 'ALL' or s.status = 'ALL') and p.addr = s.paddr order by st.value desc, p.spid asc, s.username asc, s.osuser asc
16。查看锁（lock）情况
select /*+ RULE */ ls.osuser os_user_name, ls.username user_name, decode(ls.type, 'RW', 'Row wait enqueue lock', 'TM', 'DML enqueue lock', 'TX', 'Transaction enqueue lock', 'UL', 'User supplied lock') lock_type, o.object_name object, decode(ls.lmode, 1, null, 2, 'Row Share', 3, 'Row Exclusive', 4, 'Share', 5, 'Share Row Exclusive', 6, 'Exclusive', null) lock_mode, o.owner, ls.sid, ls.serial# serial_num, ls.id1, ls.id2 from sys.dba_objects o, ( select s.osuser, s.username, l.type, l.lmode, s.sid, s.serial#, l.id1, l.id2 from v$session s, v$lock l where s.sid = l.sid ) ls where o.object_id = ls.id1 and o.owner <> 'SYS' order by o.owner, o.object_name17。查看等待（wait）情况
SELECT v$waitstat.class, v$waitstat.count count, SUM(v$sysstat.value) sum_value FROM v$waitstat, v$sysstat WHERE v$sysstat.name IN ('db block gets', 'consistent gets') group by v$waitstat.class, v$waitstat.count18。查看sga情况
SELECT NAME, BYTES FROM SYS.V_$SGASTAT ORDER BY NAME ASC19。查看catched object
SELECT owner, name, db_link, namespace, type, sharable_mem, loads, executions, locks, pins, kept FROM v$db_object_cache 20。查看V$SQLAREA
SELECT SQL_TEXT, SHARABLE_MEM, PERSISTENT_MEM, RUNTIME_MEM, SORTS, VERSION_COUNT, LOADED_VERSIONS, OPEN_VERSIONS, USERS_OPENING, EXECUTIONS, USERS_EXECUTING, LOADS, FIRST_LOAD_TIME, INVALIDATIONS, PARSE_CALLS, DISK_READS, BUFFER_GETS, ROWS_PROCESSED FROM V$SQLAREA 21。查看object分类数量
select decode (o.type#,1,'INDEX' , 2,'TABLE' , 3 , 'CLUSTER' , 4, 'VIEW' , 5 , 'SYNONYM' , 6 , 'SEQUENCE' , 'OTHER' ) object_type , count(*) quantity from sys.obj$ o where o.type# > 1 group by decode (o.type#,1,'INDEX' , 2,'TABLE' , 3 , 'CLUSTER' , 4, 'VIEW' , 5 , 'SYNONYM' , 6 , 'SEQUENCE' , 'OTHER' ) union select 'COLUMN' , count(*) from sys.col$ union select 'DB LINK' , count(*) from 22。按用户查看object种类
select u.name schema, sum(decode(o.type#, 1, 1, NULL)) indexes, sum(decode(o.type#, 2, 1, NULL)) tables, sum(decode(o.type#, 3, 1, NULL)) clusters, sum(decode(o.type#, 4, 1, NULL)) views, sum(decode(o.type#, 5, 1, NULL)) synonyms, sum(decode(o.type#, 6, 1, NULL)) sequences, sum(decode(o.type#, 1, NULL, 2, NULL, 3, NULL, 4, NULL, 5, NULL, 6, NULL, 1)) others from sys.obj$ o, sys.user$ u where o.type# >= 1 and u.user# = o.owner# and u.name <> 'PUBLIC' group by u.name order by sys.link$ union select 'CONSTRAINT' , count(*) from sys.con$23。有关connection的相关信息
1）查看有哪些用户连接
select s.osuser os_user_name, decode(sign(48 - command), 1, to_char(command), 'Action Code #' || to_char(command) ) action, p.program oracle_process, status session_status, s.terminal terminal, s.program program, s.username user_name, s.fixed_table_sequence activity_meter, '' query, 0 memory, 0 max_memory, 0 cpu_usage, s.sid, s.serial# serial_num from v$session s, v$process p where s.paddr=p.addr and s.type = 'USER' order by s.username, s.osuser2）根据v.sid查看对应连接的资源占用等情况
select n.name, v.value, n.class,n.statistic# from v$statname n, v$sesstat v where v.sid = 71 and v.statistic# = n.statistic# order by n.class, n.statistic#3）根据sid查看对应连接正在运行的sql
select /*+ PUSH_SUBQ */command_type, sql_text, sharable_mem, persistent_mem, runtime_mem, sorts, version_count, loaded_versions, open_versions, users_opening, executions, users_executing, loads, first_load_time, invalidations, parse_calls, disk_reads, buffer_gets, rows_processed,sysdate start_time,sysdate finish_time,'>' || address sql_address,'N' status from v$sqlareawhere address = (select sql_address from v$session where sid = 71)
24．查询表空间使用情况
select a.tablespace_name "表空间名称",
100-round((nvl(b.bytes_free,0)/a.bytes_alloc)*100,2) "占用率(%)",
round(a.bytes_alloc/1024/1024,2) "容量(M)",
round(nvl(b.bytes_free,0)/1024/1024,2) "空闲(M)",
round((a.bytes_alloc-nvl(b.bytes_free,0))/1024/1024,2) "使用(M)",
Largest "最大扩展段(M)",
to_char(sysdate,'yyyy-mm-dd hh24:mi:ss') "采样时间"
from (select f.tablespace_name,
sum(f.bytes) bytes_alloc,
sum(decode(f.autoextensible,'YES',f.maxbytes,'NO',f.bytes)) maxbytes
from dba_data_files f
group by tablespace_name) a,
(select f.tablespace_name,
sum(f.bytes) bytes_free
from dba_free_space f
group by tablespace_name) b,
(select round(max(ff.length)*16/1024,2) Largest,
ts.name tablespace_name
from sys.fet$ ff, sys.file$ tf,sys.ts$ ts
where ts.ts#=ff.ts# and ff.file#=tf.relfile# and ts.ts#=tf.ts#
group by ts.name, tf.blocks) c
where a.tablespace_name = b.tablespace_name and a.tablespace_name = c.tablespace_name
25. 查询表空间的碎片程度
select tablespace_name,count(tablespace_name) from dba_free_space group by tablespace_name
having count(tablespace_name)>10;
alter tablespace name coalesce;
alter table name deallocate unused;
create or replace view ts_blocks_v as
select tablespace_name,block_id,bytes,blocks,'free space' segment_name from dba_free_space
union all
select tablespace_name,block_id,bytes,blocks,segment_name from dba_extents;
select * from ts_blocks_v;
select tablespace_name,sum(bytes),max(bytes),count(block_id) from dba_free_space
group by tablespace_name;
26。查询有哪些数据库实例在运行
select inst_name from v$active_instances;