oracle-查询执行速度慢的sql
Oracle 查询每天执行慢的SQL 2014-12-11 18:00:04
分类： Oracle
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工作中的您是否有 想对每天慢的sql进行查询、汇总或者行优化等情况，如下SQL希望对您有帮助
--- 查询每天执行慢的SQL：
SELECT S.SQL_TEXT,
S.SQL_FULLTEXT,
S.SQL_ID,
ROUND(ELAPSED_TIME / 1000000 / (CASE
WHEN (EXECUTIONS = 0 OR NVL(EXECUTIONS, 1 ) = 1) THEN
1
ELSE
EXECUTIONS
END),
2) "执行时间'S'",
S.EXECUTIONS "执行次数",
S.OPTIMIZER_COST "COST",
S.SORTS,
S.MODULE, --连接模式（JDBC THIN CLIENT：程序）
-- S.LOCKED_TOTAL,
S.PHYSICAL_READ_BYTES "物理读",
-- S.PHYSICAL_READ_REQUESTS "物理读请求",
S.PHYSICAL_WRITE_REQUESTS "物理写",
-- S.PHYSICAL_WRITE_BYTES "物理写请求",
S.ROWS_PROCESSED "返回行数",
S.DISK_READS "磁盘读",
S.DIRECT_WRITES "直接路径写",
S.PARSING_SCHEMA_NAME,
S.LAST_ACTIVE_TIME
FROM GV$SQLAREA S
WHERE ROUND(ELAPSED_TIME / 1000000 / (CASE
WHEN (EXECUTIONS = 0 OR NVL(EXECUTIONS, 1 ) = 1) THEN
1
ELSE
EXECUTIONS
END),
2) > 5 --100 0000微秒=1S
AND S.PARSING_SCHEMA_NAME = USER
AND TO_CHAR(S.LAST_LOAD_TIME, 'YYYY-MM-DD') =
TO_CHAR( SYSDATE, 'YYYY-MM-DD' )
AND S.COMMAND_TYPE IN (2 , 3, 5, 6 , 189)
ORDER BY "执行时间'S'" DESC;
/* SQL中 COMMAND_TYPE意义:
2：INSERT3：SELECT6：UPDATE7：DELETE189：MERGE
详情可通过查找V$SQLCOMMAND视图 */
V$SQLCOMMAND 官网解释：http://docs.oracle.com/cd/E11882_01/server.112/e40402/dynviews_3066.htm#REFRN30632
part2:
性能查询的常用几个sql
--查询最慢的sql
select * from (
select parsing_user_id,executions,sorts
command_type,disk_reads,sql_text from v$sqlarea order by disk_reads desc
)where rownum<10
--查询对应session
select SE.SID,SE.SERIAL#,PR.SPID,
SE.USERNAME,SE.STATUS,SE.TERMINAL,
SE.PROGRAM,SE.MODULE,
SE.SQL_ADDRESS,ST.EVENT,
ST.P1TEXT,SI.PHYSICAL_READS,SI.BLOCK_CHANGES from v$session se,v$session_wait st,
v$sess_io si,v$process pr
where st.SID=se.SID and st.SID=si.SID
AND SE.PADDR=PR.ADDR
AND SE.SID>6
AND ST.WAIT_TIME=0
AND ST.EVENT NOT LIKE '%SQL%'
ORDER BY PHYSICAL_READS DESC;
SELECT sql_address FROM V$SESSION SS,V$SQLTEXT TT
WHERE SS.SQL_HASH_VALUE=TT.HASH_VALUE AND SID=439;
v$sqltext：存储的是完整的SQL,SQL被分割
v$sqlarea：存储的SQL 和一些相关的信息，比如累计的执行次数，逻辑读，物理读等统计信息（统计）
v$sql：内存共享SQL区域中已经解析的SQL语句。（即时）
根据sid查找完整sql语句：
select sql_text from v$sqltext a where a.hash_value = (select sql_hash_value from v$session b where b.sid = '&sid' )
order by piece asc
select a.CPU_TIME,--CPU时间 百万分之一（微秒）
a.OPTIMIZER_MODE,--优化方式
a.EXECUTIONS,--执行次数
a.DISK_READS,--读盘次数
a.SHARABLE_MEM,--占用shared pool的内存多少
a.BUFFER_GETS,--读取缓冲区的次数
a.COMMAND_TYPE,--命令类型(3:select,2:insert;6:update;7delete;47:pl/sql程序单元)
a.SQL_TEXT,--Sql语句
a.SHARABLE_MEM,
a.PERSISTENT_MEM,
a.RUNTIME_MEM,
a.PARSE_CALLS,
a.DISK_READS,
a.DIRECT_WRITES,
a.CONCURRENCY_WAIT_TIME,
a.USER_IO_WAIT_TIME
from SYS.V_$SQLAREA a
WHERE PARSING_SCHEMA_NAME = 'CHEA_FILL'--表空间
order by a.CPU_TIME desc
引用：http://jenniferok.iteye.com/blog/700985
从V$SQLAREA中查询最占用资源的查询
select b.username username,a.disk_reads reads,
a.executions exec,a.disk_reads/decode(a.executions,0,1,a.executions) rds_exec_ratio,
a.sql_text Statement
from v$sqlarea a,dba_users b
where a.parsing_user_id=b.user_id
and a.disk_reads > 100000
order by a.disk_reads desc;
a.executions exec,a.disk_reads/decode(a.executions,0,1,a.executions) rds_exec_ratio,
a.sql_text Statement
from v$sqlarea a,dba_users b
where a.parsing_user_id=b.user_id
and a.disk_reads > 100000
order by a.disk_reads desc;
用buffer_gets列来替换disk_reads列可以得到占用最多内存的sql语句的相关信息。
v$sql：内存共享SQL区域中已经解析的SQL语句。（即时）
列出使用频率最高的5个查询：
select sql_text,executions
from (select sql_text,executions,
rank() over
(order by executions desc) exec_rank
from v$sql)
where exec_rank <=5;
from (select sql_text,executions,
rank() over
(order by executions desc) exec_rank
from v$sql)
where exec_rank <=5;
消耗磁盘读取最多的sql top5：
select disk_reads,sql_text
from (select sql_text,disk_reads,
dense_rank() over
(order by disk_reads desc) disk_reads_rank
from v$sql)
where disk_reads_rank <=5;
select disk_reads,sql_text
from (select sql_text,disk_reads,
dense_rank() over
(order by disk_reads desc) disk_reads_rank
from v$sql)
where disk_reads_rank <=5;
找出需要大量缓冲读取（逻辑读）操作的查询：
select buffer_gets,sql_text
from (select sql_text,buffer_gets,
dense_rank() over
(order by buffer_gets desc) buffer_gets_rank
from v$sql)
where buffer_gets_rank<=5;
from (select sql_text,buffer_gets,
dense_rank() over
(order by buffer_gets desc) buffer_gets_rank
from v$sql)
where buffer_gets_rank<=5;
v$sqlarea字段定义：http://happyhou.blog.sohu.com/60494432.html
SQL_TEXT |
VARCHAR2(1000) |
First thousand characters of the SQL text for the current cursor |
SQL_ID |
VARCHAR2(13) |
SQL identifier of the parent cursor in the library cache |
SHARABLE_MEM |
NUMBER |
Amount of shared memory used by a cursor. If multiple child cursors exist, then the sum of all shared memory used by all child cursors. |
PERSISTENT_MEM |
NUMBER |
Fixed amount of memory used for the lifetime of an open cursor. If multiple child cursors exist, the fixed sum of memory used for the lifetime of all the child cursors. |
RUNTIME_MEM |
NUMBER |
Fixed amount of memory required during execution of a cursor. If multiple child cursors exist, the fixed sum of all memory required during execution of all the child cursors. |
SORTS |
NUMBER |
Sum of the number of sorts that were done for all the child cursors |
VERSION_COUNT |
NUMBER |
Number of child cursors that are present in the cache under this parent |
LOADED_VERSIONS |
NUMBER |
Number of child cursors that are present in the cache and have their context heap (KGL heap 6) loaded |
OPEN_VERSIONS |
NUMBER |
The number of child cursors that are currently open under this current parent |
USERS_OPENING |
NUMBER |
Number of users that have any of the child cursors open |
FETCHES |
NUMBER |
Number of fetches associated with the SQL statement |
EXECUTIONS |
NUMBER |
Total number of executions, totalled over all the child cursors |
END_OF_FETCH_COUNT |
NUMBER |
Number of times this cursor was fully executed since the cursor was brought into the library cache. The value of this statistic is not incremented when the cursor is partially executed, either because it failed during the execution or because only the first few rows produced by this cursor are fetched before the cursor is closed or re-executed. By definition, the value of theEND_OF_FETCH_COUNT column should be less or equal to the value of the EXECUTIONS column. |
USERS_EXECUTING |
NUMBER |
Total number of users executing the statement over all child cursors |
LOADS |
NUMBER |
Number of times the object was loaded or reloaded |
FIRST_LOAD_TIME |
VARCHAR2(19) |
Timestamp of the parent creation time |
INVALIDATIONS |
NUMBER |
Total number of invalidations over all the child cursors |
PARSE_CALLS |
NUMBER |
Sum of all parse calls to all the child cursors under this parent |
DISK_READS |
NUMBER |
Sum of the number of disk reads over all child cursors |
DIRECT_WRITES |
NUMBER |
Sum of the number of direct writes over all child cursors |
BUFFER_GETS |
NUMBER |
Sum of buffer gets over all child cursors |
APPLICATION_WAIT_TIME |
NUMBER |
Application wait time |
CONCURRENCY_WAIT_TIME |
NUMBER |
Concurrency wait time |
CLUSTER_WAIT_TIME |
NUMBER |
Cluster wait time |
USER_IO_WAIT_TIME |
NUMBER |
User I/O Wait Time |
PLSQL_EXEC_TIME |
NUMBER |
PL/SQL execution time |
JAVA_EXEC_TIME |
NUMBER |
Java execution time |
ROWS_PROCESSED |
NUMBER |
Total number of rows processed on behalf of this SQL statement |
COMMAND_TYPE |
NUMBER |
Oracle command type definition |
OPTIMIZER_MODE |
VARCHAR2(25) |
Mode under which the SQL statement was executed |
PARSING_USER_ID |
NUMBER |
User ID of the user that has parsed the very first cursor under this parent |
PARSING_SCHEMA_ID |
NUMBER |
Schema ID that was used to parse this child cursor |
KEPT_VERSIONS |
NUMBER |
Number of child cursors that have been marked to be kept using the DBMS_SHARED_POOL package |
ADDRESS |
RAW(4 | 8) |
Address of the handle to the parent for this cursor |
HASH_VALUE |
NUMBER |
Hash value of the parent statement in the library cache |
OLD_HASH_VALUE |
NUMBER |
Old SQL hash value |
MODULE |
VARCHAR2(64) |
Contains the name of the module that was executing at the time that the SQL statement was first parsed as set by calling DBMS_APPLICATION_INFO .SET_MODULE |
MODULE_HASH |
NUMBER |
Hash value of the module that is named in the MODULEcolumn |
ACTION |
VARCHAR2(64) |
Contains the name of the action that was executing at the time that the SQL statement was first parsed as set by calling DBMS_APPLICATION_INFO .SET_ACTION |
ACTION_HASH |
NUMBER |
Hash value of the action that is named in the ACTIONcolumn |
SERIALIZABLE_ABORTS |
NUMBER |
Number of times the transaction fails to serialize, producing ORA-08177 errors, totalled over all the child cursors |
CPU_TIME |
NUMBER |
CPU time (in microseconds) used by this cursor for parsing/executing/fetching |
ELAPSED_TIME |
NUMBER |
Elapsed time (in microseconds) used by this cursor for parsing/executing/fetching |
IS_OBSOLETE |
VARCHAR2(1) |
Indicates whether the cursor has become obsolete (Y ) or not (N ). This can happen if the number of child cursors is too large. |
CHILD_LATCH |
NUMBER |
Child latch number that is protecting the cursor |
PROGRAM_ID |
NUMBER |
Program identifie |
posted on 2016-04-28 15:06 gaomatlab 阅读(10364) 评论(0) 编辑 收藏 举报
