Java Oracle thin and OCI connectivity for failover of multiple databases

Java Oracle thin and OCI connectivity for failover of multiple databases

First, Thin way

This method is easy to use and is not uncommon.

The URL is
jdbc:oracle:thin:@ (description= (Load_balance=on)
(Address= (PROTOCOL=TCP) (host=127.0.0.1) (port=1521))
(Address= (PROTOCOL=TCP) (host=10.132.111.14) (port=1521))
(Connect_data= (service_name=busi_db)))

The load_balance=on indicates that the load is on, and Java creates the session connection in random way;
Load_banlance=off indicates that the load is closed, and Java creates the session connection in a sequential fashion, with only
The second database is selected for session connection only if there is a problem with the first database that cannot be connected.

Ii. mode of OCI

under Windows system :

1. Detailed program deployment of the native need to install OracleClient: path is oralc_home;

2. In the system environment variable path append ;%O Racle_home%/bin .

3. Add the Nls_lang system environment variable to the system environment variable whose character set is consistent with the database and client as follows:Nls_lang=simplified Chinese_china. ZHS16GBK

4. If CLASSPATH is configured in the system environment variable, append to the variable ;%O Racle_home%/lib

5. OracleClient the JDBC driver (Oracle_home/jdbc/lib/ojdbc*.jar) to your own project project.

Under UNIX or Linux systems:

1. Detailed program deployment of the native need to install OracleClient: path is oralc_home;

2. The System environment variable path setting such as the following:

Path= $ORACLE _home/bin: $PATH

Export PATH

3. System environment variables Ld_library_path settings such as the following:

Ld_library_path= $ORACLE _home/lib: $LD _library_path

Export Ld_library_path

4. Set the nls_lang variable in the system environment variable whose character set is consistent with the database and client as follows:

nls_lang= "Simplified Chinese_china. ZHS16GBK "

Export Nls_lang

5. OracleClient's own JDBC driver (Oracle_home/jdbc/lib/ojdbc*.jar) is tested in its own project to maintain consistency with the database. Otherwise, easy appears unable to connect the exception of the local method.

Here is a list of configurations for a Oracleclienttnsnames.ora file such as the following:
ha_db =
(Description_list =
(load_balance = ON)
(FAILOVER = ON)
(DESCRIPTION =
(Address_list =
(Load_balance=off)
(Failover=on)
(ADDRESS = (PROTOCOL = TCP) (HOST = 127.0.0.1) (PORT = 1521))
)
(Connect_data =
(service_name = DB1)
(instance_name = DB1)
(Failover_mode= (type=session) (Method=basic) (retries=4) (Delay=1))
)
)
(DESCRIPTION =
(Address_list =
(Load_balance=off)
(Failover=on)
(ADDRESS = (PROTOCOL = TCP) (HOST = 10.132.111.14) (PORT = 1521))
)
(Connect_data =
(service_name = DB2)
(instance_name = DB2)
(Failover_mode= (type=session) (Method=basic) (retries=4) (Delay=1))
)
)
(DESCRIPTION =
(Address_list =
(Load_balance=off)
(Failover=on)
(ADDRESS = (PROTOCOL = TCP) (HOST = 10.112.11.161) (PORT = 1521))
)
(Connect_data =
(service_name = db3)
(instance_name = db3)
(Failover_mode= (type=session) (Method=basic) (retries=4) (Delay=1))
)
)

)

Please check the relevant information for the function of the configuration parameter.

Then, when the Java program JDBC OCI is connected, the URL is written as java:oracle:oci: @ha_db can.

Java Oracle thin and OCI connectivity for failover of multiple databases