Oracle里的常用命令詳解日志治理 1.forcing log switches sql> alter system switch logfile;2.forcing checkpoints sql> alter system checkpoint; 3.adding online redo log groups sql> alter database add logfile [group 4] sql> ('/disk3/log4a.rdo','/disk4/log4b.rdo') size 1m; 4.adding online redo log members sql> alter database add logfile member sql> '/disk3/log1b.rdo' to group 1, sql> '/disk4/log2b.rdo' to group 2; 5.changes the name of the online redo logfile sql> alter database rename file 'c:/oracle/oradata/oradb/redo01.log' sql> to 'c:/oracle/oradata/redo01.logƌ.drop online redo log groups sql> alter database drop logfile group 3; 7.drop online redo log members sql> alter database drop logfile member 'c:/oracle/oradata/redo01.logƎ.clearing online redo log files sql> alter database clear [unarchived] logfile 'c:/oracle/log2a.rdoƏ.using logminer analyzing redo logfiles a. in the init.ora specify utl_file_dir = ' ' b. sql> execute dbms_logmnr_d.build('oradb.ora','c:oracleoradblog'); c. sql> execute dbms_logmnr_add_logfile('c:oracleoradataoradbredo01.log', sql> dbms_logmnr.new); d. sql> execute dbms_logmnr.add_logfile('c:oracleoradataoradbredo02.log', sql> dbms_logmnr.addfile); e. sql> execute dbms_logmnr.start_logmnr(dictfilename=>'c:oracleoradblogoradb.ora'); f. sql> select * from v$logmnr_contents(v$logmnr_dictionary,v$logmnr_parameters sql> v$logmnr_logs); g. sql> execute dbms_logmnr.end_logmnr; 表空間治理 1.create tablespaces sql> create tablespace tablespace_name datafile 'c:oracleoradatafile1.dbf' size 100m, sql> 'c:oracleoradatafile2.dbf' size 100m minimum extent 550k [logging/nologging] sql> default storage (initial 500k next 500k maxextents 500 pctinccease 0) sql> [online/offline] [permanent/temporary] [extent_management_clause] 2.locally managed tablespace sql> create tablespace user_data datafile 'c:oracleoradatauser_data01.dbf' sql> size 500m extent management local uniform size 10m; 3.temporary tablespace sql> create temporary tablespace temp tempfile 'c:oracleoradatatemp01.dbf' sql> size 500m extent management local uniform size 10m; 4.change the storage setting sql> alter tablespace app_data minimum extent 2m; sql> alter tablespace app_data default storage(initial 2m next 2m maxextents 999); 5.taking tablespace offline or online sql> alter tablespace app_data offline; sql> alter tablespace app_data online; 6.read_only tablespace sql> alter tablespace app_data read onlywrite; 7.droping tablespace sql> drop tablespace app_data including contents; 8.enableing automatic extension of data files sql> alter tablespace app_data add datafile 'c:oracleoradataapp_data01.dbf' size 200m sql> autoextend on next 10m maxsize 500m; 9.change the size fo data files manually sql> alter database datafile 'c:oracleoradataapp_data.dbf' resize 200m; 10.Moving data files: alter tablespace sql> alter tablespace app_data rename datafile 'c:oracleoradataapp_data.dbf' sql> to 'c:oracleapp_data.dbfཇ.moving data files:alter database sql> alter database rename file 'c:oracleoradataapp_data.dbf' sql> to 'c:oracleapp_data.dbf'表 1.create a table sql> create table table_name (column datatype,column datatype]....) sql> tablespace tablespace_name [pctfree integer] [pctused integer] sql> [initrans integer] [maxtrans integer] sql> storage(initial 200k next 200k pctincrease 0 maxextents 50) sql> [loggingnologging] [cachenocache] 2.copy an existing table sql> create table table_name [loggingnologging] as subquery 3.create temporary table sql> create global temporary table xay_temp as select * from xay; on commit preserve rows/on commit delete rows 4.pctfree = (average row size - initial row size) *100 /average row size pctused = 100-pctfree- (average row size*100/available data space) 5.change storage and block utilization parameter sql> alter table table_name pctfree=30 pctused=50 storage(next 500k sql> minextents 2 maxextents 100); 6.manually allocating extents sql> alter table table_name allocate extent(size 500k datafile 'c:/oracle/data.dbf'); 7.move tablespace sql> alter table employee move tablespace users; 8.deallocate of unused space sql> alter table table_name deallocate unused [keep integer] 9.truncate a table sql> truncate table table_name; 10.drop a table sql> drop table table_name [cascade constraints]; 11.drop a column sql> alter table table_name drop column comments cascade constraints checkpoint 1000; alter table table_name drop columns continue; 12.mark a column as unused sql> alter table table_name set unused column comments cascade constraints; alter table table_name drop unused columns checkpoint 1000; alter table orders drop columns continue checkpoint 1000 data_dictionary : dba_unused_col_tabs