Oracle command Summary-log management and table empty Management

Chapter 1: Log Management

    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.log'; 

    6.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.log'; 

    8.clearing online redo log files 

    sql> alter database clear [unarchived] logfile 'c:/oracle/log2a.rdo'; 

    9.using logminer analyzing redo logfiles 

    a. in the init.ora specify utl_file_dir = ' ' 

    b. sql> execute dbms_logmnr_d.build('oradb.ora','c:\oracle\oradb\log'); 

    c. sql> execute dbms_logmnr_add_logfile('c:\oracle\oradata\oradb\redo01.log', 

    sql> dbms_logmnr.new); 

    d. sql> execute dbms_logmnr.add_logfile('c:\oracle\oradata\oradb\redo02.log', 

    sql> dbms_logmnr.addfile); 

    e. sql> execute dbms_logmnr.start_logmnr(dictfilename=>'c:\oracle\oradb\log\oradb.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; 

Chapter 2: Table space management

    1.create tablespaces 

    sql> create tablespace tablespace_name datafile 'c:\oracle\oradata\file1.dbf' size 100m, 

    sql> 'c:\oracle\oradata\file2.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:\oracle\oradata\user_data01.dbf' 

    sql> size 500m extent management local uniform size 10m; 

    3.temporary tablespace 

    sql> create temporary tablespace temp tempfile 'c:\oracle\oradata\temp01.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 only|write; 

    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:\oracle\oradata\app_data01.dbf'size 200m 

    sql> autoextend on next 10m maxsize 500m; 

    9.change the size fo data files manually 

    sql> alter database datafile 'c:\oracle\oradata\app_data.dbf'resize 200m; 

    10.Moving data files: alter tablespace 

    sql> alter tablespace app_data rename datafile 'c:\oracle\oradata\app_data.dbf' 

    sql> to 'c:\oracle\app_data.dbf'; 

    11.moving data files:alter database 

    sql> alter database rename file 'c:\oracle\oradata\app_data.dbf' 

    sql> to 'c:\oracle\app_data.dbf'; 

Chapter 3: tables

    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> [logging|nologging] [cache|nocache] 

    2.copy an existing table 

    sql> create table table_name [logging|nologging] 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