26 Ekim 2021 Salı

Oracle Streams Senkron Kullanım

Giriş
Şeklen şöyle


Senkron kullanım için adımlar burada
1. Create User & Setup Privileges : Stream Administrator rolü yaratılır
2. Create Database Links at source and target
3. Create Queue at source and target
4. Create Capture at source
5. Create Apply Process at target
6. Create Propagation at source
7. Instantiation at target
8 Start Apply at target
9. Start Capture at source

Kullanılan PL/SQL paketleri şöyle
DBMS_APPLY_ADM
DBMS_CAPTURE_ADM
DBMS_FLASHBACK
DBMS_OUTPUT
DBMS_STREAMS_ADM

DBMS_APPLY_ADM Paketi
START_APPLY(), STOP_APPLY(), DELETE_ALL_ERRORS() gibi metodlar kullanılabilir
DBMS_APPLY_ADM.START_APPLY(apply_name => 'SYNC_APPLY_1');
...
DBMS_APPLY_ADM.STOP_APPLY(apply_name => 'SYNC_APPLY_1');
DBMS_APPLY_ADM.DELETE_ALL_ERRORS(apply_name => 'SYNC_APPLY_1');
Duplicate Rows
Açıklaması şöyle
1. You cannot use Oracle Streams to replicate a table which has duplicate rows. It will not work.
2. If you don’t have unique constraint on your table in some form, you will have duplicate rows.
Create Database Links
Şöyle yaparız
--on source
CONNECT strmadmin/strmadminpw;
CREATE DATABASE LINK REP01 CONNECT TO strmadmin IDENTIFIED BY strmadminpw USING 'REP01';
select count(*) from dba_tables@REP01;

-- on target
CONNECT strmadmin/strmadminpw;
CREATE DATABASE LINK DB05 CONNECT TO strmadmin IDENTIFIED BY strmadminpw USING 'DB05';
select count(*) from dba_tables@DB05
Create Queue
Örnek
Şöyle yaparız
DBMS_STREAMS_ADM.SET_UP_QUEUE(
queue_table =>'STRADMIN.SQT_IMMEDIATE1_S', 
queue_name => 'STRADMIN.SQ_IMMEDIATE_S');
Apply
streams_type olarak APPLY verilebilir
Örnek
Şöyle yaparız.
DBMS_STREAMS_ADM.ADD_TABLE_RULES( table_name => ..., streams_type => 'apply', streams_name => ..., queue_name => ... );
Capture
streams_type olarak CAPTURE, SYNC_CAPTURE verilebilir. Açıklaması şöyle
Synchronous Mode

Synchronous Capture uses triggers on the source database to capture change data. It has no latency because the change data is captured continuously and in real-time on the source database. The change tables are populated when DML operations on the source table are committed. Hence it is titled “Synchronous” Change Data Capture.

New change data arrives automatically as DML operations on the source tables are committed. Publishers can define new change sets in the predefined SYNC_SOURCE change source or use the predefined change set, SYNC_SET. The SYNC_SET change set cannot be altered or dropped.

While the “invasive” nature of the approach of the synchronous mode of Change Data Capture adds overhead to the source database at capture time, this mode can reduce costs (as compared to attempting to extract change data using table differencing or change-value section) by simplifying the extraction of change data.

Örnek - Senkron
Şöyle yaparız. inclusion_rule FALSE verilerek capture işlemi yapılmıyor
DBMS_STREAMS_ADM.ADD_TABLE_RULES(
table_name=>'DEV110.APP_QUEUE', streams_type=>'capture', streams_name=>'CAPTURE_110DEV', queue_name=>'REP_CAPTURE_QUEUE', include_dml=>TRUE, include_ddl=>TRUE, include_tagged_lcr=> FALSE, source_database=>'DB05', inclusion_rule=>FALSE, and_condition=>NULL);

11 Ağustos 2021 Çarşamba

Maven İle Oracle JDBC Thin Driver

JDBC Thin Driver vs OCI
Açıklaması şöyle. Yani Java kullanıyorsak JDBC Thin Driver yeterli.
Oracle provides four types of drivers for their database, but I'll only enumerate the two you asked about.

The OCI driver is a type 2 JDBC driver and uses native code to connect to the database. Thus, it is only an option on platforms that have native Oracle drivers available and it is not a "pure" Java implementation.

Oracle's JDBC Thin driver is a type 4 JDBC Driver that uses Java sockets to connect directly to Oracle. It implements Oracle's SQL*Net TCP/IP protocol directly. Because it is 100% Java, it is platform independent ...
Maven
ojdbc "Oracle JDBC Driver" anlamına gelir

ojdbc11
Örnek
Şöyle yaparız
<dependency>
  <groupId>com.oracle.database.jdbc</groupId>
  <artifactId>ojdbc11</artifactId>
  <version>23.2.0.0</version>
</dependency>
ojdbc10
Örnek
Şöyle yaparız
Java 11
<dependency>
    <groupId>com.oracle.database.jdbc</groupId>
    <artifactId>ojdbc10</artifactId>
    <version>${oracle.version}</version>
</dependency>

Java 8
<dependency>
    <groupId>com.oracle.database.jdbc</groupId>
    <artifactId>ojdbc8</artifactId>
    <version>${oracle.version}</version>
</dependency>

Java 6
<dependency>
    <groupId>com.oracle.database.jdbc</groupId>
    <artifactId>ojdbc6</artifactId>
    <version>${oracle.version}</version>
</dependency>
ojdbc8
Java 8 içindir
Örnek
Şöyle yaparız
<dependency>
  <groupId>com.oracle</groupId>
  <artifactId>ojdbc8</artifactId>
  <version>19.7.0.0</version>
</dependency>
Şöyle yaparız
<dependency>
  <groupId>com.oracle.database.jdbc</groupId>
  <artifactId>ojdbc8-production</artifactId>
  <version>21.7.0.0</version>
  <type>pom</type>
</dependency>
ojdbc7
Java 8 öncesi içindir
Örnek 
Şöyle yaparız
<dependency>
  <groupId>com.oracle</groupId>
  <artifactId>ojdbc7</artifactId>
  <version>12.1.0.2</version>
</dependency>
Sınıflar
Bazı sınıflar şöyle 

Connection Pool
Oracle Universal Connection Pool kullanılabilir.

Universal Connection Pool - PoolDataSource Sınıfı

Giriş
Açıklaması şöyle. Yani 12c'den sonra JDBC sürücüsü de en az 12.1.0.2 olmalı
Prior to 12c (i.e., 12.1.0.1.0), UCP could work with any version of Oracle JDBC driver. With the new pool, UCP 12.1.0.2, it is dependent on Oracle JDBC driver 12.1.0.2.
Örnek
Şöyle yaparızOracleDataSource sınıfını kullanıyor
import oracle.ucp.jdbc.PoolDataSource;
import java.sql.Connection;
import java.sql.SQLException;

PoolDataSource ds = PoolDataSourceFactory.getPoolDataSource();
ds.setUser("...");
ds.setPassword("...");
ds.setConnectionFactoryClassName("oracle.jdbc.pool.OracleDataSource");
ds.setURL("jdbc:oracle:thin:@exampledb?TNS_ADMIN=/msdataworkshop/creds");
Connecton con = ds.getConnection();
Örnek
Şöyle yaparız.
PoolDataSource pds = PoolDataSourceFactory.getPoolDataSource();

pds.setURL(...);
pds.setUser(...);
pds.setPassword(...);
pds.setConnectionFactoryClassName("oracle.jdbc.pool.OracleDataSource");

//Setting pool properties
pds.setInitialPoolSize(5);
pds.setMinPoolSize(5);
pds.setMaxPoolSize(20);

Connection conn = pds.getConnection();
Şöyle yaparız.
int usedConnectionCount = pds.getBorrowedConnectionsCount();
int availableConnectionCotun = pds.getAvailableConnectionsCount();

22 Mayıs 2020 Cuma

Oracle NoSQL Database

Giriş
Açıklaması şöyle.
It is worth nothing that the Oracle's flagship database and their NoSQL one are separate products.