梦想有多远

今天在QQ一个朋友问了一个问题，

select t.*,t.rowid
  from cux_erp_eam_outstock_vt
 where xydw in
       (select erp_dept_name
          from base_department
         where erp_dept_name in (’D-103005–焦化公司_炼焦作业区’))
做以上查询时，没有输出，但是分开执行时就有，一开始没有想到是设计的问题，只是想到base_department的erp_dept_name可能有空的。后来才找到问题，原来是两个表的相同字段类型不一致导致的。

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使用tkprof格式化trace文件
Usage: tkprof tracefile outputfile [explain= ] [table= ] [print= ] [insert= ] [sys= ] [sort= ]

tkprof erptest_ora_27576.trc session.txt explain=system/manager aggregate=yes sys=no waits=yes sort=fchela

输入文件 格式化后的输出文件
table=schema.tablename Use ’schema.tablename’ with ‘explain=’ option.
用于指定在将执行规划写进输出文件之前，TKPROF用于临时存放执行规划所用表的架构和名称
explain=user/password Connect to ORACLE and issue EXPLAIN PLAN.
print=integer List only the first ‘integer’ SQL statements.

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一.Memory Dumps
1).Global Area
ALTER SESSION SET EVENTS ‘immediate trace name global_area level n’;
1 包含PGA
2 包含SGA
4 包含UGA
8 包含indrect memory
2).Library Cache
ALTER SESSION SET EVENTS ‘immediate trace name library_cache level n’;
1 library cache统计信息
2 包含hash table histogram
3 包含object handle
4 包含object结构（Heap 0）
3).Row Cache
ALTER SESSION SET EVENTS ‘immediate trace name row_cache level n’;
1 row cache统计信息
2 包含hash table histogram
8 包含object结构
4).Buffers
ALTER SESSION SET EVENTS ‘immediate trace name buffers level n’;
1 buffer header
2 level 1 + block header
3 level 2 + block contents
4 level 1 + hash chain
5 level 2 + hash chain
6 level 3 + hash chain
8 level 4 + users/waiters
9 level 5 + users/waiters
10 level 6 + users/waiters
5).Buffer
ALTER SESSION SET EVENTS ‘immediate trace name buffer level n’;
n为某个指定block的rdba，该命令可以转储某个block在buffer中的所有版本。
6).Heap
ALTER SESSION SET EVENTS ‘immediate trace name heapdump level level’;
1 PGA摘要
2 SGA摘要
4 UGA摘要
8 Current call(CGA)摘要
16 User call(CGA)摘要
32 Large call(LGA)摘要
1025 PGA内容
2050 SGA内容
4100 UGA内容
8200 Current call内容
16400 User call内容
32800 Large call内容
7).Sub Heap
Oracle 9.0.1版本之前
ALTER SESSION SET EVENTS ‘immediate trace name heapdump_addr level n’;
若n为subheap的地址，转储的是subheap的摘要信息
若n为subheap的地址+1，转储的则是subheap的内容
Oracle 9.2.0版本之后
ALTER SESSION SET EVENTS ‘immediate trace name heapdump_addr level n, addr m’;
其中m为subheap的地址
n为1转储subheap的摘要，n为2转储subheap的内容
8).Process State
ALTER SESSION SET EVENTS ‘immediate trace name processstate level n’;
9).System State
ALTER SESSION SET EVENTS ‘immediate trace name systemstate level n’;
10).Error State
ALTER SESSION SET EVENTS ‘immediate trace name errorstack level n’;
0 Error stack
1 level 0 + function call stack
2 level 1 + process state
3 level 2 + context area
11).Hang Analysis
ALTER SESSION SET EVENTS ‘immediate trace name hanganalyze level n’;
12).Work Area
ALTER SESSION SET EVENTS ‘immediate trace name workareatab_dump level n’;
1 SGA信息
2 Workarea Table摘要信息
3 Workarea Table详细信息
13).Latches
ALTER SESSION SET EVENTS ‘immediate trace name latches level n’;
1 latch信息
2 统计信息
14).Events
ALTER SESSION SET EVENTS ‘immediate trace name events level n’;
1 session
2 process
3 system
15).Locks
ALTER SESSION SET EVENTS ‘immediate trace name locks level n’;
16).Shared Server Process
ALTER SESSION SET EVENTS ‘immediate trace name shared_server_state level n’;
n取值为1~14
17).Background Messages
ALTER SESSION SET EVENTS ‘immediate trace name bg_messages level n’;
n为pid+1
二.File Dumps
1).Block
Oracle 7之前
ALTER SESSION SET EVENTS ‘immediate trace name blockdump level n’;
n为block的rdba
Oracle8以后
ALTER SYSTEM DUMP DATAFILE file# BLOCK block#;
ALTER SYSTEM DUMP DATAFILE file#
BLOCK MIN minimum_block#
BLOCK MAX maximum_block#;
2).Tree Dump
ALTER SESSION SET EVENTS ‘immediate trace name treedump level n’;
n为object_id
3).Undo Segment Header
ALTER SYSTEM DUMP UNDO_HEADER ’segment_name’;
4).Undo for a Transaction
ALTER SYSTEM DUMP UNDO BLOCK ’segment_name’ XID xidusn xidslot xidsqn;
5).File Header
ALTER SESSION SET EVENTS ‘immediate trace name file_hdrs level n’;
1 控制文件中的文件头信息
2 level 1 + 文件头信息
3 level 2 + 数据文件头信息
10 level 3
6).Control file
ALTER SESSION SET EVENTS ‘immediate trace name controlf level n’;
1 文件头信息
2 level 1 + 数据库信息 + 检查点信息
3 level 2 + 可重用节信息
10 level 3
7).Redo log Header
ALTER SESSION SET EVENTS ‘immediate trace name redohdr level n’;
1 控制文件中的redo log信息
2 level 1 + 文件头信息
3 level 2 + 日志文件头信息
10 level 3
8).Redo log
ALTER SYSTEM DUMP LOGFILE ‘FileName’;
ALTER SYSTEM DUMP LOGFILE ‘FileName’
SCN MIN MinimumSCN
SCN MAX MaximumSCN
TIME MIN MinimumTime
TIME MAX MaximumTime
LAYER Layer
OPCODE Opcode
DBA MIN FileNumber . BlockNumber
DBA MAX FileNumber . BlockNumber
RBA MIN LogFileSequenceNumber . BlockNumber
RBA MAX LogFileSequenceNumber . BlockNumber;
其中time = (((((yyyy - 1988)) * 12 + mm - 1) * 31 + dd - 1) * 24 + hh) * 60 + mi) * 60 + ss;
9).Loghist
ALTER SESSION SET EVENTS ‘immediate trace name loghist level n’;
1 dump控制文件中最早和最迟的日志历史项
>1 dump 2^n个日志历史项