Talip Hakan ÖZTÜRK BANKASYA – ORACLE DBA OCE, 10g OCA, 10g OCP Veritabanı Objeleri Ölçülebilirlik & Performans

Talip Hakan ÖZTÜRK  Azerbaycan Teknik Üniversitesi – Bilgisayar Müh.  BANKASYA - Oracle DBA  OCE, 10g OCA, 10g OCP  Oracle Blogger   Oracle Forum Sorumlusu ve Editörü 

 Veritabanı Objeleri – Demo  Views  Constraints  DML Triggers  DDL Triggers  B*Tree Indexes  Bitmap Indexes  Function Based Indexes  Index Organized Tables  External Tables  Synonyms  Sequence  Okuma Tutarlılığı (Read Consistency)  Kilitler (Locks) Gündem

Views  Tablo joinleri içerebilirler.  DML? Simple CREATE OR REPLACE FORCE VIEW calisanlar_v AS SELECT c.employee_id, c.first_name, c.last_name, c.hire_date FROM calisanlar c; Complex CREATE OR REPLACE FORCE VIEW calisanlar_v (min_salary, department_name) AS SELECT min(c.salary),d.department_name FROM calisanlar c, departmanlar d WHERE c.department_id=d.department_id GROUP BY d.department_name;

Constraints ALTER TABLE calisanlar ADD ( CONSTRAINT salary_check CHECK ( NVL(salary,0) >= 1000 )); insert into calisanlar (first_name,last_name, ,salary) values  Tablonun ilgili alanına uygulanan kısıtlamadır.

DML Triggers create table calisanlar_log ( user_id varchar2(10), log_date date, action varchar2(1000) ); CREATE OR REPLACE TRIGGER calisanlar_kontrol_delete BEFORE DELETE ON calisanlar REFERENCING NEW AS new OLD AS old FOR EACH ROW DECLARE BEGIN raise_application_error(-20001,'Silme islemi yapamazsiniz! DBA ile gorusunuz!'); end; delete from calisanlar where employee_id=105; CREATE OR REPLACE TRIGGER calisanlar_kontrol_insert AFTER INSERT ON calisanlar REFERENCING NEW AS new OLD AS old FOR EACH ROW DECLARE BEGIN INSERT INTO calisanlar_log (user_id,log_date,action) VALUES (USER, SYSDATE, 'calisanlar tablosuna kayıt insert edildi'); end; insert into calisanlar (first_name,last_name, ,salary) values

DDL Triggers CREATE OR REPLACE TRIGGER logon_trig AFTER LOGON ON SCHEMA BEGIN INSERT INTO log_trig_table(user_id,log_date,action) VALUES (USER, SYSDATE, 'Logging on'); END; / create table log_trig_table ( user_id varchar2(10), log_date date, action varchar2(10) ); select * from log_trig_table;

B*Tree Indexes S DEU DEN ENG SCO SPA USAAUS BEL CAN Set autotrace on SELECT * FROM CALISANLAR WHERE EMPLOYEE_ID=105; CREATE INDEX CALISANLAR_ID_X ON CALISANLAR(EMPLOYEE_ID); --ALTER SYSTEM FLUSH SHARED_POOL; --ALTER SYSTEM FLUSH BUFFER_CACHE; analyze index CALISANLAR_ID_X compute statistics;

Bitmap Indexes create table bitmap_index_demo ( value varchar2(20) ); insert into bitmap_index_demo select decode(mod(rownum,2),0,'M','F') from all_objects; create bitmap index bitmap_index_demo_idx on bitmap_index_demo(value); -- birinci session insert into bitmap_index_demo values ('M'); -- ikinci session insert into bitmap_index_demo values ('F'); -- birinci session insert into bitmap_index_demo values ('F'); create table bitmap_index_demo1 as select * from bitmap_index_demo; insert into bitmap_index_demo1 select decode(mod(rownum,2),0,'M','F') from all_objects; create index bitmap_index_demo1_idx on bitmap_index_demo1(value); -- birinci session insert into bitmap_index_demo1 values ('M'); -- ikinci session insert into bitmap_index_demo1 values ('F'); -- birinci session insert into bitmap_index_demo1 values ('F');

Function Based Indexes CREATE INDEX CALISANLAR_ID_2X ON CALISANLAR(SALARY); CREATE INDEX CALISANLAR_ID_3X ON CALISANLAR(SALARY*10/100); SELECT * FROM calisanlar WHERE SALARY*10/100>=1000;

Index Organized Tables Veriler B*Tree index yapısında saklanır. create table iot_table ( id number primary key, name varchar2(5) ) organization index; create table normal_table ( id number primary key, name varchar2(5) ); insert into iot_table values(5,'a'); commit;

External Tables create or replace directory talipdir as '/oracle/ora11g'; as sysdba grant read,write on directory talipdir to talip; as sysdba create table dblist ( CI_name varchar2(20), ID varchar2(20), logical_name varchar2(20), dbname varchar2(20), thread number, type varchar2(20), subtype varchar2(20), environment varchar2(20) ) organization external ( default directory talipdir access parameters ( records delimited by newline fields terminated by ';' ) location ('dblist.csv') )REJECT LIMIT unlimited; select * from dblist order by ci_name desc;

Synonyms ALI. HESAP_NO HESAP_NO Public Synonym To ALI.HESAP_NO VELISELIMAYSE Select * from hesap_no;  Private Synonyms  Public Synonyms create synonym ygm_test.calisanlar for talip.calisanlar; create public synonym calisanlar for talip.calisanlar;

Sequence CREATE SEQUENCE calisan_id INCREMENT BY 1 START WITH 1 MAXVALUE 100 MINVALUE 1 NOCYCLE CACHE 20 ORDER;

Session 1Session 2 10:30 UPDATE scott.emp SET sal = sal+10 WHERE ename = 'KING'; 10:32 UPDATE scott.emp SET sal = sal+20 WHERE ename = 'KING'; 10:34commit ; 10:35commit; Read Consistency

Session 1Session 2 10:30 UPDATE scott.emp SET sal = 1000 WHERE ename = 'KING'; 10:32 SELECT sal FROM scott.emp WHERE ename = 'KING'; 10:35commit ; Read Consistency

Session 1Session 2 10:30 UPDATE scott.emp SET sal = 1000 WHERE ename = 'KING'; 10:32 UPDATE scott.emp SET sal = 1500 WHERE ename = 'KING'; 10:34commit; 10:35commit ; Read Consistency

Session 1: UPDATE scott.emp SET ename = 'KING1' WHERE ename = 'KING'; (don NOT commit) Session 2: SELECT ename FROM scott.emp WHERE ename='KING' FOR UPDATE OF ename wait 10; after 10 seconds : * ERROR at line 1: ORA-30006: resource busy; acquire with WAIT timeout expired DML Locks

Deadlocks

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