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ORACLE系统查询话语

www.myexceptions.net  网友分享于：2015-08-26  浏览：19次

ORACLE系统查询语句

1、序列：

select * from dba_sequences;

2、视图：

select * from dba_views;

select * from all_views;

3、查询表名、列名、标注释：  这个比较实用，可以用于导出数据时，不用再去写一张静态数据来存储。

select * from user_col_comments；指当前这个用户下的表

select * from  all_col_comments；所有

select * from   dba_col_comments; 具备DBA权限的

4  查看某表的创建时间

select object_name,created from user_objects where object_name=upper('&table_name');

5  查看某表的大小

select sum(bytes)/(1024*1024) as "size(M)" from user_segments

where segment_name=upper('&table_name');

6  查找表中多余的重复记录，重复记录是根据单个字段(peopleId)来判断

select * from people

where peopleId in (select   peopleId from   people group by   peopleId having count(peopleId) > 1)

7  删除表中多余的重复记录，重复记录是根据单个字段(peopleId)来判断，只留有rowid最小的记录

delete from people

where peopleId in (select   peopleId from people group by   peopleId   having count(peopleId) > 1)

and rowid not in (select min(rowid) from   people group by peopleId having count(peopleId )>1)

8  查找表中多余的重复记录(多个字段)

select * from vitae a

where (a.peopleId,a.seq) in   (select peopleId,seq from vitae group by peopleId,seq having count(*) > 1)

9  删除表中多余的重复记录(多个字段)，只留有rowid最小的记录

delete from vitae a

where (a.peopleId,a.seq) in   (select peopleId,seq from vitae group by peopleId,seq having count(*) > 1)

and rowid not in (select min(rowid) from vitae group by peopleId,seq having count(*)>1)

10  1.GRANT 赋于权限

常用的系统权限集合有以下三个:

CONNECT(基本的连接),   RESOURCE(程序开发),   DBA(数据库管理)

常用的数据对象权限有以下五个:

ALL   ON   数据对象名,   SELECT   ON   数据对象名,   UPDATE   ON   数据对象名,

DELETE   ON   数据对象名,     INSERT   ON   数据对象名,       ALTER     ON   数据对象名

GRANT   CONNECT,   RESOURCE   TO   用户名;

GRANT   SELECT   ON   表名   TO   用户名;

GRANT   SELECT,   INSERT,   DELETE   ON表名   TO   用户名1,   用户名2;

2.REVOKE   回收权限

REVOKE   CONNECT,   RESOURCE   FROM   用户名;

REVOKE   SELECT   ON   表名   FROM   用户名;

REVOKE   SELECT,   INSERT,   DELETE   ON表名   FROM   用户名1,   用户名2;

表名为 dept ，其中name字段是中文，下面分别实现按照单位名称的笔划、部首和拼音排序。

1: //按照笔划排序

2: select * from dept order by nlssort(name,'NLS_SORT=SCHINESE_STROKE_M');

3: //按照部首排序

4: select * from dept order by nlssort(name,'NLS_SORT=SCHINESE_RADICAL_M');

5: //按照拼音排序，此为系统的默认排序方式

6: select * from dept order by nlssort(name,'NLS_SORT=SCHINESE_PINYIN_M'); 注意，该SQL指令并非标准指令，在SQLServer下面的实现方式并不相同。

optimizer_cost 值越大影响越大.

/* 查询锁 */

SELECT /*+ ordered */

o.object_name, o.object_type, l.locked_mode, s.machine, l.os_user_name,

s.terminal, l.oracle_username, o.subobject_name, s.program, s.module

FROM v$session s, v$locked_object l, dba_objects o

WHERE l.object_id = o.object_id

AND s.sid = l.session_id

/* 查询锁 */

SELECT /*+ ordered */

o.object_name, o.object_type, k.type, l.locked_mode lock_mode_value,

DECODE(l.locked_mode, 0, 'NONE',

1, 'NULL',

2, 'ROW SHARE',

3, 'ROW EXCLUSIVE',

4, 'SHARE',

5, 'SHARE ROW EXCLUSIVE',

6, 'EXCLUSIVE') lock_mode,

s.sid, s.serial#,

s.machine, l.os_user_name, s.terminal, l.oracle_username, o.subobject_name,

s.program, s.module

FROM v$session s, v$locked_object l, v$lock k, dba_objects o

WHERE l.object_id = o.object_id

AND s.sid = l.session_id

AND s.sid = k.sid

ORDER BY s.sid

/* 查询事务中的锁和相关信息 */

SELECT /*+ ordered */

o.object_name, o.object_type,k.type, l.locked_mode, s.machine, l.os_user_name,

s.terminal, l.oracle_username, o.subobject_name, s.program, s.module,

k.id1, k.id2, k.request, k.ctime, k.block,

t.status, t.start_time, t.xidusn seg_num, r.name seg_name

FROM v$rollname r, v$lock k, v$session s, v$locked_object l, dba_objects o,

v$transaction t

WHERE l.object_id = o.object_id

AND s.sid = l.session_id

AND s.sid = k.sid

AND t.xidusn = r.usn

AND l.xidusn = t.xidusn

/* 缓冲区命中率 */

/* The data in V$SYSSTAT reflects the logical and physical reads for all buffer pools

within one set of statistics */

/* 50%以下(危险,立即增加缓冲区缓存) 95%以上分配过度 90%-95%为调整的目标 */

SELECT ROUND((1 - (phy.value / (cur.value + con.value))) * 100,

3) || '%' "Buffer Cache Hit Ratio"

FROM v$sysstat phy, v$sysstat cur, v$sysstat con

WHERE phy.name = 'physical reads'

AND cur.name = 'db block gets'

AND con.name = 'consistent gets'

/* 每个Buffer Pool的命中率 */

select name "Buffer Pool",1 - (physical_reads / (db_block_gets + consistent_gets)) "Buffer Pool Hit Ratio"

from v$buffer_pool_statistics order by name;

/* 查询某个会话的缓冲区命中率(查询的响应时间比较长) */

SELECT s.sid, s.username,

ROUND((1 - phy_read.value / (cons_get.value + block_get.value)) * 100, 3) || '%'

"BUFFER_HIT_RATIO"

FROM v$session s,

v$sesstat cons_get, v$statname cons,

v$sesstat block_get, v$statname block,

v$sesstat phy_read, v$statname phy

WHERE s.sid = cons_get.sid

AND cons_get.statistic# = cons.statistic#

AND cons.name = 'consistent gets'

AND s.sid = block_get.sid

AND block_get.statistic# = block.statistic#

AND block.name = 'db block gets'

AND s.sid = phy_read.sid

AND phy_read.statistic# = phy.statistic#

AND phy.name = 'physical reads'

AND cons_get.value + block_get.value > 0

ORDER BY 1

/* 查询确定Shared Pool Memory的利用率 */

/* 60%-80%利用是最佳的 */

SELECT (used / value) * 100 SHARED_POOL_USAGE_RATIO

FROM v$parameter p,

(SELECT SUM(bytes) used

FROM v$sgastat

WHERE pool = 'shared pool'

AND name <> 'free memory')

WHERE p.name = 'shared_pool_size'

/* 共享池空闲率 */

/* 40%-100% 分配过度, 10%-20% 分配最佳*/

SELECT (s.bytes / p.value)* 100 shared_pool_free_ratio

FROM v$parameter p, v$sgastat s

WHERE s.pool = 'shared pool'

AND s.name = 'free memory'

AND p.name = 'shared_pool_size'

/* Library Cache Reloads*/

/* 如果reload的值大于1%就得增加共享池的大小 */

SELECT SUM(pins) "Executions", SUM(reloads) "Cache Misses",

SUM(reloads) / SUM(pins)

FROM v$librarycache

/* 查询排序的情况 */

SELECT *

FROM v$sysstat

WHERE name LIKE '%sorts%'

/* 查询磁盘排序和内存排序的比率(应该低于5%)*/

SELECT disk.value "Disk", mem.value "Mem",

(disk.value / mem.value) * 100 "Ratio"

FROM v$sysstat mem, v$sysstat disk

WHERE mem.name = 'sorts (memory)'

AND disk.name = 'sorts (disk)'

/* 查询正在做的事务 */

SELECT xid, status, start_time, xidusn seg_num, r.name seg_name

FROM v$transaction t, v$rollname r

WHERE t.xidusn = r.usn

/* 查询父表外键引用的子表 */

SELECT a.table_name 外键表, a.constraint_name 外键名, b.column_name 外键字段,

c.table_name 主键表, a.r_constraint_name 主键名,

c.column_name 主键字段

FROM user_constraints a, user_cons_columns b, user_cons_columns c

WHERE a.constraint_type = 'R'

AND a.constraint_name = b.constraint_name

AND a.r_constraint_name = c.constraint_name

AND LOWER(c.table_name) = '&table_name'

/* XXX 等待 XXX 用户 */

SELECT w.sid || ' wait ' || w.blocking_session

FROM v$session a, v$session w

WHERE w.blocking_session = a.sid

/* Oracle中的一些进程信息, 便于在solaris中去kill进程 */

SELECT s.SID, s.serial#, spid AS "PROCESS OR THREAD", s.osuser, s.program,

NVL2(s.blocking_session, 'WAIT ' || s.blocking_session,

'NO WAIT') "WAIT INFO",

s.machine, s.terminal

FROM v$process p, v$session s, v$session w

WHERE p.addr = s.paddr

AND s.blocking_session = w.sid(+);

/* Parse */

SELECT name,value

FROM v$sysstat

WHERE name LIKE '%parse%'

/* 监测用户执行的SQL1 */

SELECT s.*

FROM v$sql s, dba_users u

WHERE s.parsing_user_id = u.user_id

AND u.username = UPPER('&username');

/* 监测用户执行的SQL2 */

SELECT s.parse_calls, s.*

FROM v$sql s, dba_users u

WHERE s.parsing_user_id = u.user_id

AND u.username = UPPER('&username')

AND s.module = 'JDBC Thin Client'

--AND s.module = 'TOAD 9.0.0.160'

AND s.sql_text LIKE 'SELECT%'

/* 查询pga命中率有关的信息 */

SELECT * FROM v$pga_target_advice

PGA的参数pga_aggregate_target

/* UNDO_TABLESPACE大小的配置 */

SELECT ((SELECT value

FROM v$parameter

WHERE name = 'undo_retention') *

(SELECT MAX(undoblks)

FROM v$undostat) *

(SELECT value

FROM v$parameter

WHERE name = 'db_block_size')) / 1024 / 1024 * (1 + 0.2)|| ' MB'

undo_tablespace_size

FROM dual

/* 查询表空间使用情况这里的使用率还包含了回收站里的对象(不包括临时表空间)(在11g上用) */

SELECT c.ts#, c.name,  d.contents, d.extent_management, e.file_bytes, c.used,

SUBSTR (c.used / e.file_bytes * 100, 1, 5)

FROM (SELECT name, ts#, SUM(used) used

FROM (SELECT a.allocated_space * (SELECT value  -- 查询db_block_size当前值

FROM v$parameter

WHERE name = 'db_block_size') / 1024/ 1024 used,

b.ts#, b.name

FROM v$filespace_usage a, v$tablespace b

WHERE a.tablespace_id = b.ts#)

GROUP BY name, ts#) c,

dba_tablespaces d,

(SELECT ts#, SUM(bytes) / 1024/ 1024 file_bytes

FROM v$datafile

GROUP BY ts#) e

WHERE c.name = d.tablespace_name

AND e.ts# = c.ts#

ORDER BY ts#

-- 这里还有条语句但是效率不高, 查询数据字典还是尽量查询v$或者x$开头的视图

SELECT a.a1 表空间名称, c.c2 类型, c.c3 区管理,

b.b2 / 1024 / 1024 表空间大小m, (b.b2 - a.a2) / 1024 / 1024 已使用m,

SUBSTR ((b.b2 - a.a2) / b.b2 * 100, 1, 5) 利用率

FROM (SELECT   tablespace_name a1, SUM (NVL (BYTES, 0)) a2

FROM dba_free_space

GROUP BY tablespace_name) a,

(SELECT   tablespace_name b1, SUM (BYTES) b2

FROM dba_data_files

GROUP BY tablespace_name) b,

(SELECT tablespace_name c1, contents c2, extent_management c3

FROM dba_tablespaces) c

WHERE a.a1 = b.b1 AND c.c1 = b.b1

ORDER BY 表空间名称

/* 查询使用表相关的SQL */

SELECT *

FROM v$tempseg_usage t1, v$sql t2

WHERE t1.sql_id = t2.sql_id

/* 将常用的包缓存到SHARED_POOL中  */

BEGIN

DBMS_SHARED_POOL.KEEP('DBMS_ALERT');

DBMS_SHARED_POOL.KEEP('DBMS_DDL');

DBMS_SHARED_POOL.KEEP('DBMS_DESCRIBE');

DBMS_SHARED_POOL.KEEP('DBMS_LOCK');

DBMS_SHARED_POOL.KEEP('DBMS_OUTPUT');

DBMS_SHARED_POOL.KEEP('DBMS_PIPE');

DBMS_SHARED_POOL.KEEP('DBMS_SESSION');

DBMS_SHARED_POOL.KEEP('DBMS_SHARED_POOL');

DBMS_SHARED_POOL.KEEP('DBMS_STANDARD');

DBMS_SHARED_POOL.KEEP('DBMS_UTILITY');

DBMS_SHARED_POOL.KEEP('STANDARD');

END;

/

/* 解决索引赤色 */

1, 分析索引结构

ANALYZE INDEX &index_name VALIDATE STRUCTURE

2, 查询索引是否对称, 如果比率超过20%就应该重建索引

SELECT ROUND(del_lf_rows_len / lf_rows_len * 100) || '%' BALANCE_RATIO

FROM index_stats

WHERE name = UPPER('&index_name')

3, 重建索引

ALTER INDEX &index_name REBUILD ONLINE;

/* 定位数据库中的热点块 */

SELECT b.obj object, o.owner, o.object_name, o.object_type,

o.status, b.dbarfil file#, b.dbablk block#, b.tch touches

FROM x$bh b, dba_objects o

WHERE b.tch > 10

AND o.object_id = b.obj

ORDER BY b.tch DESC

/* 字典缓存的命中率 */

SELECT parameter, gets, getmisses, usage, (gets - getmisses) / gets WHEN 0 THEN NULL

ELSE gets END

FROM v$rowcache

/* 查询回闪区的容量 */

SELECT SUBSTR (name, 1, 30) name, space_limit AS total, space_used AS used,

space_used / space_limit AS pct_used, space_reclaimable AS reclaimable,

number_of_files AS files

FROM v$recovery_file_dest;

参数

db_recovery_file_dest_size --回闪区的大小

/* Oracle中对内存分配的建议 */

SELECT * FROM v$pga_target_advice

SELECT * FROM v$pga_target_advice_histogram

SELECT * FROM v$mttr_target_advice

SELECT * FROM v$px_buffer_advice

SELECT * FROM v$db_cache_advice

SELECT * FROM v$sga_target_advice

SELECT * FROM v$shared_pool_advice

SELECT * FROM v$java_pool_advice

SELECT * FROM v$streams_pool_advice

-- 查找低劣的SQL

/* RMAN */

crosscheck archivelog all;

delete expired archivelog all;

-- 查询隐含参数

SELECT a.indx, a.ksppinm, a.ksppdesc, a.ksppiflg,

a.ksppilrmflg, b.ksppstvl, b.ksppstdf, b.ksppstvf

FROM x$ksppi a, x$ksppcv b

WHERE a.indx = b.indx

AND ksppinm LIKE '\_%' ESCAPE '\'

--得到服务器ip

set serverout on

exec dbms_output.put_line(utl_inaddr.get_host_address);

-- 有关latch的

/* miss的百分比，不要超过1% */

SELECT name,

gets, misses * 100 / DECODE (gets, 0, 1, gets) misses,

spin_gets * 100 / DECODE (misses, 0, 1, misses) spins,

immediate_gets igets,

immediate_misses * 100 / DECODE (immediate_gets, 0, 1, immediate_gets) imisses

FROM v$latch

WHERE gets <> 0

ORDER BY gets DESC

SELECT a.name, a.gets gets,

a.misses * 100 /

DECODE(a.gets, 0, 1, a.gets) miss,

TO_CHAR(a.spin_gets * 100 / DECODE(a.misses, 0, 1, a.misses), '990.9') || TO_CHAR (a.sleep6 * 100 / DECODE (a.misses, 0, 1, a.misses), '90.9') cspins,

TO_CHAR (a.sleep1 * 100 / DECODE (a.misses, 0, 1, a.misses), '90.9') || TO_CHAR (a.sleep7 * 100 / DECODE (a.misses, 0, 1, a.misses), '90.9') csleep1,

TO_CHAR (a.sleep2 * 100 / DECODE (a.misses, 0, 1, a.misses), '90.9') || TO_CHAR (a.sleep8 * 100 / DECODE (a.misses, 0, 1, a.misses), '90.9') csleep2,

TO_CHAR (a.sleep3 * 100 / DECODE (a.misses, 0, 1, a.misses), '90.9') || TO_CHAR (a.sleep9 * 100 / DECODE (a.misses, 0, 1, a.misses), '90.9') csleep3,

TO_CHAR (a.sleep4 * 100 / DECODE (a.misses, 0, 1, a.misses), '90.9') || TO_CHAR (a.sleep10 * 100 / DECODE (a.misses, 0, 1, a.misses), '90.9') csleep4,

TO_CHAR (a.sleep5 * 100 / DECODE (a.misses, 0, 1, a.misses), '90.9') || TO_CHAR (a.sleep11 * 100 / DECODE (a.misses, 0, 1, a.misses), '90.9') csleep5

FROM v$latch a

WHERE a.misses <> 0

ORDER BY 2 DESC

--DBMS_METADATA.GET_DDL

1.得到一个表或索引的ddl语句

SELECT DBMS_METADATA.GET_DDL('TABLE','DEPT','SCOTT') FROM DUAL;

select dbms_metadata.get_ddl('INDEX','PK_DEPT','SCOTT') from dual;

2.得到一个用户下的所有表，索引，存储过程的ddl

SELECT DBMS_METADATA.GET_DDL(U.OBJECT_TYPE, u.object_name)

FROM USER_OBJECTS u

where U.OBJECT_TYPE IN ('TABLE','INDEX','PROCEDURE');

3.得到所有表空间的ddl语句

SELECT DBMS_METADATA.GET_DDL('TABLESPACE', TS.tablespace_name)

FROM DBA_TABLESPACES TS;

4.得到所有创建用户的ddl

SELECT DBMS_METADATA.GET_DDL('USER',U.username)

FROM DBA_USERS U;

和处理AWR快照相关

SELECT * FROM DBA_HIST_SNAPSHOT ORDER BY SNAP_ID DESC

BEGIN

DBMS_WORKLOAD_REPOSITORY.CREATE_SNAPSHOT;

END;

/

BEGIN

DBMS_WORKLOAD_REPOSITORY.DROP_SNAPSHOT_RANGE(56, 57);

END;

/

SQL> @?/rdbms/admin/awrrpt.sql

-- 查询无效索引

SELECT INDEX_NAME FROM USER_INDEXES WHERE STATUS <> 'VALID' AND PARTITIONED = 'NO';

SELECT INDEX_NAME, PARTITION_NAME FROM USER_IND_PARTITIONS WHERE STATUS <> 'USABLE';

-- 生成重建索引的语句

SELECT 'ALTER INDEX ' || INDEX_NAME || ' REBUILD' FROM USER_INDEXES WHERE STATUS <> 'VALID' AND PARTITIONED = 'NO';

SELECT 'ALTER INDEX ' || INDEX_NAME || ' REBUILD PARTITION ' || PARTITION_NAME FROM USER_IND_PARTITIONS WHERE STATUS <> 'USABLE';

-- 收集统计信息

cascade设置为true is also gather columns and index’s statistics

exec DBMS_STATS.GATHER_TABLE_STATS(ownname=> 'SA' , tabname=>'T_PRODUCT_SUBSCRIBE',estimate_percent=>100, degree=>1, cascade=> TRUE);

exec DBMS_STATS.SET_TABLE_STATS(ownname=> 'SA' , tabname=>'T_PRODUCT_SUBSCRIBE', numrows=>1000000);

11g上自动统计信息相关

select client_name,status from Dba_Autotask_Client;

select log_date,status from dba_scheduler_job_run_details

where job_name='BSLN_MAINTAIN_STATS_JOB' order by log_date desc;

select job_name,state from dba_scheduler_jobs where job_name='BSLN_MAINTAIN_STATS_JOB' ;

BEGIN DBMS_AUTO_TASK_ADMIN.DISABLE(CLIENT_NAME => 'auto optimizer stats collection', OPERATION => NULL, WINDOW_NAME => NULL); END;

-- 从操作系统上杀数据库连接

ps -ef | grep LOCAL | grep -v grep | awk '{print $2}' | xargs kill -9

跟踪会话

SELECT P.PID, P.SPID

FROM V$PROCESS P, V$SESSION S

WHERE P.ADDR = S.PADDR

AND S.SID = 154

-- 使用V$PROCESS中的列SPID

ORADEBUG SETOSPID XX

-- 使用V$PROCESS中的PID

ORADEBUG SETORAPID XX

-- 开启跟踪

ORADEBUG EVENT 10046 TRACE NAME CONTEXT FOREVER, LEVEL 12

ORADEBUG TRACEFILE_NAME

-- 关闭跟踪

ORADEBUG EVENT 10046 TRACE NAME CONTEXT OFF

tkprof C:\01\orcl_ora_652.trc C:\01\orcl_ora_652.txt aggregate=yes sys=no sort=prscnt

--

SELECT plan_table_output FROM table(DBMS_XPLAN.DISPLAY_CURSOR('4ba4mf4mknjvr', 0, 'ALL'));

SELECT plan_table_output FROM table(DBMS_XPLAN.DISPLAY_CURSOR('4ba4mf4mknjvr', 0, 'iostats last'));

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