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Not able to connect oracle Database while using Cluster type HOST

I'm facing the following errors while connecting oracle DB, I'm using spring boot JDBC template to connect to database. The errors are below,
Exception in thread "main" java.lang.Exception: java.sql.SQLRecoverableException: IO Error: The Network Adapter could not establish the connection
at com.falabella.util.OracleDB.main(OracleDB.java:70)
Caused by: java.sql.SQLRecoverableException: IO Error: The Network Adapter could not establish the connection
Caused by: oracle.net.ns.NetException: The Network Adapter could not establish the connection
at oracle.net.nt.ConnStrategy.execute(ConnStrategy.java:392)
Caused by: java.net.UnknownHostException: NODE-01: nodename nor servname provided, or not known
Below are my finding, My database server host having the cluster and it has two nodes, like below,
Cluster (wood.clsuter.com)
| NODE01 (wood-01)
| NODE02 (wood-02)
My connection string is like this, jdbc:oracle:thin:#wood-clsuter.com:1531/service_name
When I'm using the cluster name in the connection string, I'm facing the below error
Caused by: java.net.UnknownHostException: wood-01: nodename nor servname provided, or not known
Whereas if I use any of the node name in the connection string , able to connect Data base without any issue, the working connection string is like below,
jdbc:oracle:thin:#wood-01.com:1531/service_name or
jdbc:oracle:thin:#wood-02.com:1531/service_name
Since I need to use my DB requests as load balancing, I need to use the cluster name instead of slave nodes,
I would like to know the root cause of this issue, such kind of production environment issues,
Could you please help me out with this?

You need to change connect string to:
"jdbc:oracle:thin:#(DESCRIPTION=(FAILOVER=ON)(LOAD_BALANCE=ON)(ADDRESS_LIST=(ADDRESS=(PROTOCOL=TCP)(HOST=wood-01.com)(PORT = 1531))(ADDRESS = (PROTOCOL = TCP)(HOST = wood-02.com)(PORT = 1531)))(CONNECT_DATA=(SERVICE_NAME =service_name)(FAILOVER_MODE=(TYPE=select)(METHOD=basic))))"

Database connectivity issue in my code

Oracle JDBC Driver Registered!
The connection is established.
The statement object is created.
Exception in thread "main" java.sql.SQLException: ORA-00955: name is already used by an existing object
at oracle.jdbc.driver.DatabaseError.throwSqlException(DatabaseError.java:112)
at oracle.jdbc.driver.T4CTTIoer.processError(T4CTTIoer.java:331)
at oracle.jdbc.driver.T4CTTIoer.processError(T4CTTIoer.java:288)
at oracle.jdbc.driver.T4C8Oall.receive(T4C8Oall.java:743)
at oracle.jdbc.driver.T4CStatement.doOall8(T4CStatement.java:207)
at oracle.jdbc.driver.T4CStatement.executeForRows(T4CStatement.java:946)
at oracle.jdbc.driver.OracleStatement.doExecuteWithTimeout(OracleStatement.java:1169)
at oracle.jdbc.driver.OracleStatement.executeUpdateInternal(OracleStatement.java:1615)
at oracle.jdbc.driver.OracleStatement.executeUpdate(OracleStatement.java:1580)
at conn1.main(conn1.java:17)
I am having no error in the code but still, I'm not able to make a table.

ORA-00955 name is already used by an existing object.
The table name that you are trying to create by using you code also already exists so try with some other name

Teradata createClob: function not supported in this version. Is this a bug or a feature?

I am trying to test createClob() method
String conStr = "jdbc:teradata://...";
Class.forName("com.teradata.jdbc.TeraDriver");
Connection conn = DriverManager.getConnection(conStr, "user", "pass");
Clob clobTest = conn.createClob();
However it throws the following error
Exception in thread "main" java.sql.SQLException: [Teradata JDBC Driver] [TeraJDBC 15.00.00.20] [Error 165] [SQLState HY000] createClob: function not supported in this version
at com.teradata.jdbc.jdbc_4.util.ErrorFactory.makeDriverJDBCException(ErrorFactory.java:94)
at com.teradata.jdbc.jdbc_4.util.ErrorFactory.makeDriverJDBCException(ErrorFactory.java:69)
at com.teradata.jdbc.jdbc_4.TDSession.createClob(TDSession.java:1479)
I downloaded the latest version of jdbc
Why the error? What does it mean ?

The javadoc of createClob() says:
SQLException - if an object that implements the Blob interface can not be constructed, this method is called on a closed connection or a database access error occurs.
SQLFeatureNotSupportedException - if the JDBC driver does not support this data type
So technically this should have thrown a SQLFeatureNotSupportedException if Teradata does not support blobs, but that is just a minor 'bug'.
The only thing you can do is file an improvement request to ask them to implement this.

IO Exception: "/root/test outside /opt/h2/DB

currently I installed the H2 database, but when I the launch the program and I try to access it from my browser (http://localhost:8082/login.do), I get this error:
IO Exception: "/root/test outside /opt/h2/DB" [90028-192] 90028/90028 (Aide) org.h2.jdbc.JdbcSQLException: IO Exception: "/root/test outside /opt/h2/DB" [90028-192]
at org.h2.message.DbException.getJdbcSQLException(DbException.java:345)
at org.h2.message.DbException.get(DbException.java:179)
at org.h2.message.DbException.get(DbException.java:155)
at org.h2.engine.ConnectionInfo.setBaseDir(ConnectionInfo.java:182)
at org.h2.jdbc.JdbcConnection.<init>(JdbcConnection.java:114)
at org.h2.jdbc.JdbcConnection.<init>(JdbcConnection.java:102)
at org.h2.Driver.connect(Driver.java:72)
at org.h2.server.web.WebServer.getConnection(WebServer.java:735)
at org.h2.server.web.WebApp.login(WebApp.java:955)
at org.h2.server.web.WebApp.process(WebApp.java:211)
at org.h2.server.web.WebApp.processRequest(WebApp.java:170)
at org.h2.server.web.WebThread.process(WebThread.java:133)
at org.h2.server.web.WebThread.run(WebThread.java:89)
at java.lang.Thread.run(Thread.java:745)
How I can fixe this ?

Just add a single "." before the name of your database. For example this is the jdbc url for my database: jdbc:h2:tcp://localhost:9101/~/test and I'll change it to this to work: jdbc:h2:tcp://localhost:9101/~./test. I've read in a forum that this bug relates to H2.

you should change the form jdbc url
and the h2-data which is you start h2 server data path
jdbc:h2:/h2-data/test

Error in connecting to Orient DB via JDBC Drivers

I am trying to connect to Orient DB running in Distributed mode and I am getting following error
Exception in thread "main" com.orientechnologies.orient.core.exception.OSerializationException:
Error on unmarshalling field 'members' in record #-1:-1 with value:
I am using :
OrientDB Version: orientdb-community-1.7-rc and
JDBC Version: OrientDB JDBC Driver 1.7-rc2-SNAPSHOT ALL
Below is my code:
public static void main(String[] args) throws ClassNotFoundException, SQLException {
Class.forName("com.orientechnologies.orient.jdbc.OrientJdbcDriver");
Connection connection = (OrientJdbcConnection) DriverManager.getConnection("jdbc:orient:remote:localhost/VANET", "root", "*****");
}
database "VANET" as per the DB connection String above, is present in OrientDB and I able to access and create classes in VANET using OrientDB Studio.
I have already referred to and tried code as per. But no luck yet.
Please help me resolve this issue.
A little more details about the error I am getting
Exception in thread "main" com.orientechnologies.orient.core.exception.OSerializationException: Error on unmarshalling field 'members' in record #-1:-1 with value:
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:57)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
at java.lang.reflect.Constructor.newInstance(Constructor.java:526)
at com.orientechnologies.common.log.OLogManager.exception(OLogManager.java:162)
at com.orientechnologies.orient.core.serialization.serializer.record.string.ORecordSerializerSchemaAware2CSV.fromString(ORecordSerializerSchemaAware2CSV.java:543)
at com.orientechnologies.orient.core.serialization.serializer.record.string.ORecordSerializerStringAbstract.fromStream(ORecordSerializerStringAbstract.java:80)
at
... * <I removed these lines >* ...
at com.orientechnologies.orient.jdbc.OrientJdbcConnection.<init>(OrientJdbcConnection.java:49)
at com.orientechnologies.orient.jdbc.OrientJdbcDriver.connect(OrientJdbcDriver.java:46)
at java.sql.DriverManager.getConnection(DriverManager.java:571)
at java.sql.DriverManager.getConnection(DriverManager.java:215)
at org.poc.orientdb.jdbc.OrientJDBC.main(OrientJDBC.java:49)
Caused by: java.lang.NullPointerException
at com.orientechnologies.orient.core.record.ORecordSchemaAwareAbstract.getSchemaClass(ORecordSchemaAwareAbstract.java:82)
at com.orientechnologies.orient.core.serialization.serializer.record.string.ORecordSerializerSchemaAware2CSV.fromString(ORecordSerializerSchemaAware2CSV.java:445)
... 28 more