My confrontations with oracle

November 4, 2008

Index

Filed under: oracle — John Jacob @ 11:43 pm

CRS-0223: Resource has placement error while using SRVCTL

Configure heterogeneous connection from Oracle DB to PostgreSQL DB

Make “n” number of connections to your DB using script in windows/unix

Restore the RMAN backup of a RAC to a Single Instance

Get Metadata of an Object in Oracle

Recovery of UNDO tablespace in a Non Archive Log mode Database

No quota on USERS tablespace? Then no EXPDP

Setting up Oracle VM using iSCSI storage

How to identify the type(32 or 64bit) of software installed ?

Recover from loss of Active redo log file

Recovery from the loss of Inactive redo log file

Recovery of non system datafile [ without backup ]

Recovery of Non System datafile [ while the database is closed ]

Recovery of Non System datafile [ while the database is open ]

Recovery of system01.dbf datafile

Tailor your Oracle account

DBA Handbook ?

OPatch failed with error code 73 ??

ORA-12541: TNS:no listener ??

Hardening Oracle Security ??

Who is referencing my table ??

Table Compression in Oracle

Oracle Recovery Scenarios

Securing oracle agents

Oracle RAC installation on Solaris SPARC 64 bit

Setting up APEX on a Standby Database Server

ORA-12560: TNS:protocol adapter error and oradim

Install Oracle in english on a machine with non english OS

Removing the semaphores of a ‘KILL’ed oracle instance

Relink -ing binaries of Oracle RDBMS and Oracle Agent

Process Monitor in Windows

Installing BUG fix 5749953-ONS SIGBUS ERROR AFTER INSTALL PATCHSET 10.2.0.3 FOR CRS

Installing patchset 10.2.0.3 on RAC RDBMS

Update RAC nodelist using runInstaller -updateNodeList

Revoke exp/imp from non privileged oracle users

Empty/Remove Oracle Listener.log files







November 16, 2009

Space required by oracle to store a character/string

One of the challenges in working with Oracle and Globalization is in identifying how much space oracle requires to store a particular alphabet,especially when the database uses a Unicode Character Set. The Unicode DB Characterset AL32UTF8 is a multi byte characterset. For an ASCII character, oracle(with AL32UTF8) need only 1 byte, where as for a Japanese character (hiragana,katakana or kanji), it would require either 3 or 4 bytes. Most of the Japanese characters are 3 bytes, but as more number of kanaji’s are accepeted for daily use, it becomes evident that oracle would require more bytes to store them.

To see how much space a character occupies, one can use the oracle vsize(‘<string>’) or dump(’string’) functions. Both these functions gives the size in bytes.

Let’s see how much space(in bytes) Oracle Db with  AL32UTF8 characterset requires tp store the word ‘tokyo’ in English and Japanese (Hiragana, Full Width Katakana, Half Width Katakana and Kanji).

English
select vsize(‘tokyo’) from dual;
5
select dump(‘tokyo’) from dual;
Typ=96 Len=5: 116,111,107,121,111

Japanese-Hiragana
select vsize(‘とうきょう’) from dual;
15
select dump(‘とうきょう’) from dual;
Typ=96 Len=15: 227,129,168,227,129,134,227,129,141,227,130,135,227,129,134

Japanese-Full Width Katakana
select vsize(‘トウキョウ’) from dual;
15
select dump(‘トウキョウ’) from dual;
Typ=96 Len=15: 227,131,136,227,130,166,227,130,173,227,131,167,227,130,166


Japanese-Half Width Katakana

select vsize(‘トウキョウ’) from dual;
15
select dump(‘トウキョウ’) from dual;
Typ=96 Len=15: 239,190,132,239,189,179,239,189,183,239,189,174,239,189,179

Japanese-Kanji
select vsize(‘東京’) from dual;
6
select dump(‘東京’) from dual;
Typ=96 Len=6: 230,157,177,228,186,172

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