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Oracle Grid Infrastructure srvctl options for

Usage: srvctl add database -db <db_unique_name> -oraclehome <oracle_home> [-dbtype {RACONENODE | RAC | SINGLE} [-server <server_list>] [-instance <inst_name>] [-timeout <timeout>]] [-domain <domain_name>] [-spfile <spfile>] [-pwfile <password_file_path>] [-role {PRIMARY | PHYSICAL_STANDBY | LOGICAL_STANDBY | SNAPSHOT_STANDBY | FAR_SYNC}] [-startoption <start_options>] [-stopoption <stop_options>] [-startconcurrency <start_concurrency>] [-stopconcurrency <stop_concurrency>] [-dbname <db_name>] [-policy {AUTOMATIC | MANUAL | NORESTART}] [-serverpool "<serverpool_list>" [-pqpool <pq_server_pools>]] [-node <node_name>] [-diskgroup "<diskgroup_list>"] [-acfspath "<acfs_path_list>"] [-eval] [-fixed] [-verbose]
Usage: srvctl config database [-db <db_unique_name> [-all] | -serverpool <serverpool_name>] [-verbose]
Usage: srvctl start datab…

MySQL Percona Tool Kit

Kill queries running longer than 60s:
pt-kill --busy-time 60 --kill
Print, do not kill, queries running longer than 60s:
pt-kill --busy-time 60 --print
Print all login processes:
pt-kill --match-state login --print --victims all
Find all tables created more than a day ago, which use the MyISAM engine, and print their names:
 pt-find --ctime +1 --engine MyISAM
Find InnoDB tables and convert them to MyISAM:
pt-find --engine InnoDB --exec "ALTER TABLE %D.%N ENGINE=MyISAM"
Find empty tables in the test and junk databases, and delete them:
pt-find --empty junk test --exec-plus "DROP TABLE %s"
Find tables more than five gigabytes in total size:
pt-find --tablesize +5G
Summarize MySQL information nicely:
pt-mysql-summary --user=root
Diff MySQL configuration files and server variables:
Diff host1 config from SHOW VARIABLES against host2:
pt-config-diff h=host1 h=host2
Diff config from [mysqld] section in my.cnf against host1 config:
pt-config-diff /etc/my.cnf h=host1
Diff the [mysqld] section …

My SQL Daily SQL

Get list of tables with particular column
TABLE_NAME NOT REGEXP "^test_.*(_archive)|(_new)|(_old)$" AND
COLUMN_NAME = '<column_name>' AND
TABLE_SCHEMA ='<schema_name>'

Find number of connections:
SHOW STATUS WHERE `variable_name` = 'Threads_connected';

Find if some table is locked:
`Database` LIKE '[DBNAME]' AND In_use > 0;

Find all foreign keys on a table:
REFERENCED_TABLE_NAME = '<table_name>';

Oracle Gather Schema | Table Statistics | Extended Statistics | method_opt

Select Histograms for tables
SELECT column_name, num_distinct, histogram FROM   user_tab_col_statistics WHERE  table_name = '<table_name>';

Gather tables stats using DBMS_STATS for table
exec dbms_stats.gather_schema_stats
ownname => '<owner_name>',
options => 'GATHER AUTO',
estimate_percent => dbms_stats.auto_sample_size,
method_opt  => 'FOR ALL COLUMNS SIZE 1',
cascade => true,
degree => 10,
granularity => 'ALL'

exec dbms_stats.gather_schema_stats
ownname=> 'SAMAPPL',
estimate_percent => dbms_stats.auto_sample_size,
method_opt => 'FOR ALL COLUMNS SIZE 1',
cascade=> true,
degree => 10
Extended statistics Ref.:

method_opt options
FOR COLUMNS SIZE 254 <column_name>

Retrive Exadata Version and Configuration Information

Option 1: Use DBMS_LOB package to get cell configuration information, as column CONFVAL is CLOB
spool confval.txt and search for text make in text file you will see get value in tag <makeModel>  </makeModel>

set pagesize 0
SELECT dbms_lob.substr(CONFVAL,4000,1) from V$CELL_CONFIG;
spool off

This option is good if you don't  have privilege to access storage node and can't execute command Cellcli. You would be able to find out interleaving attribute about Celldisk also as follows.


Explore about interleaving attribute of Celldisk at

Option 2:
From Tanel Podder Blog. I have modified some format to display Make Model properly.
COL cv_cellname       HEAD CELL_NAME        FOR A30
COL cv_cell_path      HEAD CELL_PATH        FOR A30
COL cv_cellversion    HEAD CE…

Oracle ADRCI - Automatic Diagnostic Repository Command Interpreter

adrci - Automatic Diagnostic Repository Command Interpreter

$ adrci
adrci> show homes
-- Set home for Oracle Databsae
adrci> set home
-- List incidents
adrci> show incidents
-- Pack incident for incident numbver
adrci> ips pack incident <incident_no> in /tmp
-- Show incident information in brief
adrci> show incident -mode brief -p "incident_id=<incident_no>"
-- Pack incident for problem key (Get problem key by commnad show incidents)
adrci> ips create package problemkey "ORA 600 [qmtGetBaseType]"
-- Pack incident by time (Get time record by commnd show incidents)
adrci> IPS CREATE PACKAGE TIME '2017-08-23 11:31:44.296000 -07:00' to '2017-08-22 08:32:16.394000 -07:00'


Drop Tuning Set of Oracle Database

Tuning Set Name : Test_TOP_SQL_1503437315950

select name from dba_sqlset;
select * from dba_sqlset where name like 'Test%';
Dropping SQL Task
select name from dba_sqlset;
execute dbms_sqltune.drop_sqlset('Test_TOP_SQL_1503437315950');
You could get an error, if it is reference to advisory task
Get advisory task name
select description, created, owner  from DBA_SQLSET_REFERENCES  where sqlset_name = 'Test_TOP_SQL_1503437315950';
task: SQL_TUNING_1503437363054
select owner,description, created,last_modified from DBA_ADVISOR_TASKS where task_name = 'SQL_TUNING_1503437363054';
execute dbms_sqltune.drop_tuning_task('SQL_TUNING_1503437363054');
execute DBMS_SQLTUNE.drop_sqlset (sqlset_name => 'Test_TOP_SQL_1503437315950');
If you can't drop SQL Set then check whether record exist in work load repository or not
SELECT count(*)  FROM wri$_sqlset_definitions a, wri$_sqlset_references b  WHERE = 'Test_TOP_SQL_1503437315950'  …

Smart scan for ASM disk group in Exadata

Enable smart scan for ASM Disk group while creating disk group in Exadata

DISK 'o/*/DATA*'
          'content.type' = 'data',


Check cell smart scan is enables for ASM disk or not:

 Make sure to connect ASM instance, if you connect to DB instance you won't find value.

SELECT AS diskgroup, SUBSTR(,1,24) AS name, SUBSTR(a.value,1,24) AS value FROM V$ASM_DISKGROUP dg, V$ASM_ATTRIBUTE a
WHERE dg.group_number = a.group_number and a.NAME = 'cell.smart_scan_capable';

EXADATA - Importance of Cellinit.ora and Cellip.ora files
Cellinit.ora and Cellip.ora
After Oracle Exadata Storage Server is configured, …

Kfod tool to inspect ASM disk in Exadata environment

Oracle kfod command line tool for ASM disk inspection:

kfod tool is located in grid home's bin directory.

List optinos for kfod toll using

$kfod -h
_asm_a/llow_only_raw_disks              KFOD allow only raw devices [_asm_allow_only_raw_disks=(TRUE)/FALSE]
_asm_l/ibraries         ASM Libraries[_asm_libraries=lib1,lib2,...]
_asms/id                ASM Instance[_asmsid=sid]
_b/oot          Running in pre-install env (boot=TRUE/FALSE)
_f/lexinfo              Provide flexinfo      (_flexinfo=TRUE/FALSE)
_p/atch_lib             Patchlib [_patch_lib=<asmclntsh_path>]
_u/ser          OS Username
asm_/diskstring         ASM Diskstring [asm_diskstring=discoverystring, discoverystring ...]
asmc/ompatibility               Include diskgroup ASM compatibility [asmcompatibility=TRUE/(FALSE)]
cli/ent_cluster         client cluster name
clus_/version           cluster version
clust/er                KFOD cluster [cluster=TRUE/(FALSE)]
db_/unique_name         db_unique_name for ASM instance…

Oracle Parallel Server Option in Explain Plan

Oracle parallel option:
Parallel option parameter in int.ora:

parallel_degree_level                        integer     100
parallel_degree_limit                        string      CPU
parallel_degree_policy                      string      AUTO
parallel_execution_message_size     integer     15343
parallel_max_servers                        integer     743
parallel_min_servers                         integer     76
parallel_min_time_threshold            string      AUTO
parallel_server                                   boolean     TRUE
parallel_server_instances                  integer     4
parallel_servers_target                      integer     374
parallel_threads_per_cpu                  integer     2

In an explain plan PX stands for Parallel processing.
PX Send are producer
PX Receiver receiver
PX Coordinator
PX COORDINATOR FORCED SERIAL operation means that, although the plan looks like a parallel execution, Oracle effectively will run this serially at execution time.
IN-OUT col…

Oracle Generate Explain Plan and plan statistics for SQL statement

Option 1: Display sql statement execution plan and sql execution statistics also. set pagesize 0
set linesize 5000
spool plan_q1.log
set auto trace on
 spool off Explain plan could lie explore at Kerry Osborne's Blog -
Option 2: Use DBMS_XPLAN, get explain plan from awr, using SQL_ID.
set pagesize 0
set linesize 5000
spool plan_q1.log
select * from table(dbms_xplan.display_awr('sql_id'));
spool off Options for SQL statement:
SELECT plan_table_output FROM TABLE(DBMS_XPLAN.DISPLAY('plan_table',null,'basic +predicate +cost'));
SELECT plan_table_output FROM TABLE(DBMS_XPLAN.DISPLAY('plan_table',null,'typical -cost -bytes'));
SELECT plan_table_output FROM TABLE(DBMS_XPLAN.DISPLAY('plan_table',null,'basic +note'));
Select plan_table_output From table(dbms_xplan.display_cursor(null,null,'TYPICAL');

Find out location of OCR and Voting Disk for Oracle RAC environment

Find out OCR Location for RAC environment:-
Option 1: Get the ocr location form file ocr.loc location at /etc/oracle
cat /etc/oracle/ocr.loc
Option 2: Execute ocrcheck utility form grid home. Typical grid home is Typical grid home is /u01/app/<version>/grid/bin
./ocr check
Find out location of Voting disk:-
Option 1: Query V$ASM_DISK view.
If it is Exadata you would be able to see path as o/cell_ip_address/cell_griddisk_name. i.e. o/
Option 2: Use utility crsctl. crsctl is location in bin directory of grid home. Typical grid home is /u01/app/<version>/grid/bin
./crsctl query css votedisk

MySQL mysqladmin

mysqladmin utility:-

mysqladmin is use for administrative operations. Check the server's configuration, current status and other task.

$mysqladmin [options] command [command-arg] [command [command-arg]] ...

create db_name - To create new database.

debug - Write debug information to error log.

drop db_name - Delete the database and tables.

extended-status - Display server status variables and their values.

flush-hosts - Flush all the information in host cache.

flush-logs [log_type ...] - Flush all logs.

flush-privileges - Reload the grant tables it is same as reload.

flush-status - Clear status variables

flush-tables - Flush all tables.

flush-threads - Flush the thread cache.

kill id,id,... - Kill server threads.

password new_password - Set a new password.

ping - Check whether the server is available.

processlist - Show a list of active server threads.

reload - Reload the grant tables.

refresh - Flush all tables and close and open log files.

shutdown - Stop the server.


MySQL NDB Cluster Installation for Data, SQL and Management Node

Management node: It manages the other nodes within the NDB Cluster, provides configuration data, start and stop nodes, running backups. As it manages the configuration of the other nodes, it should be started first, before any other node. Use ndb_mgmd to start it.
It also maintains a log of cluster activities. Management clients can connect to the management server and check the cluster's status.
Data node: It stores cluster data. There are as many data nodes as there are replicas, times the number of fragments. For example, with two replicas, each having two fragments, you need four data nodes. One replica is good for data storage, but no redundancy. For redundancy and high availability 2 more nodes are recommended.To start data node use ndbd or ndbmtd. Tables are normally stored completely in memory, that's why it can be refer as in-memory database. Some data can be stored on disk.
SQL node: It accesses the cluster data. It is a traditional MySQL server that uses the NDBCLUSTER…

Oracle Daily SQL

Enable System-wide tracing: alter system set events '10046 trace name context forever,level 12'; Disabled in all sessions alter system set events '10046 trace name context off'; Session Tracing alter session set tracefile_identifier='10046'; alter session set timed_statistics = true; alter session set statistics_level=all; alter session set max_dump_file_size = unlimited; alter session set events '10046 trace name context forever,level 12'; crsctl for Oracle RAC ./crsctl start cluster ./crsctl check crs Make column to CLOB ALTER TABLE TABLE_NAME MODIFY (COLUMN_NAME LONG); ALTER TABLE TABLE_NAME MODIFY (COLUMN_NAME CLOB); RENAME <TABLE_NAME> TO <NEW_TABLE_NAME>; Rename column, change data type, drop column ALTER TABLE TABLE_NAME RENAME COLUMN COLUMN_NAME TO COLUMN_NAME1; ALTER TABLE TABLE_NAME MODIFY (COLUMN_NAME VARCHAR2(10)); ALTER TABLE TABLE_NAME DROP COLUMN COLUMN_NAME; Create Primary Key ALTER TABLE TABLE_NAME ADD CONSTRAINT CONSTRAINT_NAME PRIMARY KEY (COL…