Develop Reference

DB2OLEDB Driver and error messages in SQLException from SQL Server 2016

We are using SQL Server 2016 with a linked server to zDB2 (mainframe) via Microsoft OLE DB Provider for DB2 Version 5.0.
When executing a failing SQL statement remote on a linked server (zDB2) the error description is clear in SQL studio but useless in Java.
Example of statement (missing schema name):
EXEC (N'UPDATE TABLENAME SET COLUMN1=''SOMEVALUE'' WHERE COLUMN2= ''032'' ') AT ZDB2
Gives the following result in SQL Studio:
OLE DB provider "DB2OLEDB" for linked server "ZDB2" returned message "DB2GRP.TABLENAME IS AN UNDEFINED NAME SQLSTATE: 42704, SQLCODE: -204".
Msg 7215, Level 17, State 1, Line 6
Could not execute statement on remote server 'ZDB2'.
But the following result in a Java SQLException:
com.microsoft.sqlserver.jdbc.SQLServerException: Could not execute statement on remote server 'ZDB2'.
SQL State: S0001
SQL Error code: 7215
Using a debugger and inspecting the SQL Exception object, it seems the SQLException has no other data on the error.
How can I get a more useful explanation out of the SQLException on what went wrong besides "Could not execute statement on remote server" ?
And where is the documentation of what S0001 and 7215 means ? (I already googled)
Thank you in advance.

I believe the S0001 and 7215 are responses back from the Microsoft JDBC driver. The DB2 error info is "SQLSTATE: 42704, SQLCODE: -204" which is unfortunately not showing up in the Java output. It looks like the Microsoft driver is substituting it's own sqlstate/code instead of passing along DB2's.
The -204 is "name is an undefined name" (as is stated in the text before the sqlstate and code).
http://www.ibm.com/support/knowledgecenter/SSEPEK_10.0.0/codes/src/tpc/db2z_n.html
Since you mention Java code, note that DB2 provides a JDBC driver for direct connectivity. That should at least eliminate the possibility of the MS driver interfering with the error codes returned by DB2. You typically have to get the driver and license file from your systems guys--AFAIK, they aren't publicly provided by IBM but they are included with DB2 for z/OS. But I'd recommend trying to use the IBM driver unless there's some compelling reason why you have to use the Microsoft driver--I am confused about the mention of both OLE DB Provider and JDBC.

Apparently errors from a linked server are stored as warnings on the statement rather than part of the SQLException when using Microsofts JDBC Driver.
This is how i did it:
try{
...
} catch (SQLException e) {
SQLWarning sqlWarning = currentStatement.getWarnings();
if (sqlWarning != null) {
warning = sqlWarning.getMessage();
}
}

Not able to connect with Sybase database

In java I am trying to connect with Sybase database through java program as shown below
public static void connect() {
SybDriver sybDriver = null;
Connection conn;
try {
sybDriver = (SybDriver) Class.forName(
// "com.sybase.jdbc3.jdbc.SybDriver").newInstance();
"com.sybase.jdbc2.jdbc.SybDriver").newInstance();
System.out.println("Driver Loaded");
conn = DriverManager.getConnection(url, username, password);
boolean isTrue = conn.isValid(3);
System.out.println(isTrue);
But i am getting the below exception
Driver Loaded
Exception in thread "main" java.lang.AbstractMethodError: com.sybase.jdbc2.jdbc.SybConnection.isValid(I)Z
at connectionTry.connect(connectionTry.java:97)
at connectionTry.main(connectionTry.java:23)
I have done analysis in google what i have to came up to know jconnn.jar is missing as the issue is the method isValid(I)Z is not there in jconn2.jar is not there please advise how to overcome from this error please.

The driver you are using is - based on the class name in the stacktrace - a JDBC 2 driver. The isValid method was added in Java 6 (or: JDBC 4), so you can't use it with a driver that doesn't implement it.
You either need to upgrade to a newer driver: contact Sybase for that, or simply not call the isValid method. In the code you show there is no reason to call it: you just created the connection, of course it is valid. This method is intended to check the validity of long-living connections (eg in the context of a connection pool).

AbstractMethodError is thrown when the implementation class doesn't comply to the signature defined in the abstract class. Use a compatible version of the implementation or alternatively avoid the methods that conflict.
Ideally latest version of drivers must be having matching implementations or you will have to contact sybase to fix that.

Cant connect to mariadb from java - only with mysqldeveloper [duplicate]

I am trying to connect to a database in Mariadb through a simple java application but the connection is told to be unsuccessful and an Exception is thrown. I have done the similar connection using mysql and it was working correctly. The problem is maybe with the driver here.
try{
Class.forName("org.mariadb.jdbc.Driver");
Connection connection = DriverManager.getConnection(
"jdbc:mariadb://localhost:3306/project", "root", "");
Statement statement = connection.createStatement();
String uname="xyz",pass="abc";
statement.executeUpdate("insert into user values('"+uname+"','"+pass+"')");}//end of try block
I looked up the internet for the help and came by that driver class provided by the MariaDB Client Library for Java Applications is not com.mysql.jdbc.Driver but org.mariadb.jdbc.Driver! I changed it accordingly but it seems the problem is with the very first line inside the try block. The driver is not loading at all.
Also, I have added the mysql jar file to the libraries of my java application as in the screen-shot below. Please help me through this.

It appears that you are trying to use jdbc:mariadb://... to establish a connection to a MariaDB server instance using the MySQL JDBC Driver. That probably won't work because the MySQL JDBC Driver would use jdbc:mysql://..., regardless of whether it is connecting to a MySQL server or a MariaDB server. That is, the connection string must match the driver that is being used (rather than the database server being accessed).
The MySQL and MariaDB drivers are supposed to be somewhat interchangeable, but it only seems prudent to use the MariaDB connector when accessing a MariaDB server. For what it's worth, the combination of mariadb-java-client-1.1.7.jar
and
Connection con = DriverManager.getConnection(
"jdbc:mariadb://localhost/project",
"root",
"whatever");
worked for me. I downloaded the MariaDB Client Library for Java from here:
https://downloads.mariadb.org/client-java/1.1.7/
which I arrived at via
https://downloads.mariadb.org/
Additional notes:
There is no need for a Class.forName() statement in your Java code.
The default configuration for MariaDB under Mageia may include the skip-networking directive in /etc/my.cnf. You will need to remove (or comment out) that directive if you want to connect to the database via JDBC because JDBC connections always look like "network" connections to MySQL/MariaDB, even if they are connections from localhost. (You may need to tweak the bind-address value to something like 0.0.0.0 as well.)

An additional note:
Exploring the MariaDB JDBC driver, I found this inside the url parsing file:
Project: https://github.com/MariaDB/mariadb-connector-j.git
File: src/main/java/org/mariadb/jdbc/UrlParser.java
public static UrlParser parse(final String url, Properties prop) throws SQLException {
....
if (url.startsWith("jdbc:mysql:")) {
UrlParser urlParser = new UrlParser();
parseInternal(urlParser, url, prop);
return urlParser;
} else {
if (url.startsWith("jdbc:mariadb:")) {
UrlParser urlParser = new UrlParser();
parseInternal(urlParser, "jdbc:mysql:" + url.substring(13), prop);
return urlParser;
}
}
As you can see, the string "jdbc:mariadb:" is always replaced with "jdbc:mysql:" internally. So when it comes to the MariaDB driver, whether it is :mariadb: or :mysql: it always gets parsed as "jdbc:mysql:".
No difference.
if (url.startsWith("jdbc:mariadb:")) {
....
parseInternal(urlParser, "jdbc:mysql:" + url.substring(13), prop);
....

Connecting MATLAB and MySQL with the JDBC Driver

I bought the book Undocumented MATLAB by Yair Altmam; in chapter 2.2 of the book he discusses database connectivity and using the JDBC to connect to databases. I followed the steps and text of the book. I downloaded the mysql-connector-java-5.1.30-bin.jar(from http://dev.mysql.com/downloads/connector/j/) and typed up the following code as detailed in the book:
clear all
%%Initializing JDBC driver
try
import java.sql.DriverManager;
javaclasspath('mysql-connector-java-5.1.30-bin.jar')
driverClassName = 'com.mysql.jdbc.Driver';
try
%This works when the class/JAR is on the static Java classpath
%Note: driver automatically registers with DriverManager
java.lang.Class.forName(driverClassName);
catch
try
%Try loading from the dynamic Java path
classLoader = com.mathworks.jmi.ClassLoaderManager.getClassLoaderManager;
driverClass = classLoader.loadClass(driverClassName);
catch %#ok<*CTCH>
try
%One more attempt, using the system class-loader
classLoader = java.lang.ClassLoader.getSystemClassLoader;
%An alternative, using the MATLAB Main Thread's context
%classLoader =
%java.lang.Thread.currentThread.getContextClassLoader;
driverClass = classLoader.loadClass(driverClassName);
catch
%One final attempt-load directly, like this:
driverClass = eval(driverClassName); %#ok<*NASGU>
%Or like this (if the driver name is known in advance):
driverClass = com.mysql.jdbc.Driver;
end
end
%Now manually register the driver with the DriverManager
%Note: silently fails if driver is not in the static classpath
DriverManager.registerDriver(driverClass.newInstance);
end
%continue with database processing
catch
error(['JDBC driver ' driverClassName ' not found!']);
%do some failover activity
end
%% Connecting to a database
import java.sql.*;
connStr = 'jdbc:mysql://localhost:3306/test';
con = DriverManager.getConnection(connStr,'root','1234');
Every attempt to run the code I get the following error message:
??? Java exception occurred:
java.sql.SQLException: No suitable driver found for
jdbc:mysql://localhost:3306/test
at java.sql.DriverManager.getConnection(Unknown Source)
at java.sql.DriverManager.getConnection(Unknown Source)
Error in ==> undocumentedMATLAB at 45
con = DriverManager.getConnection(connStr,'root','1234');
Has anyone experienced this problem or have any suggestion that could help me resolve it.
Thanks in advance.

My first suspicion is your java class path. Instead of:
javaclasspath('mysql-connector-java-5.1.30-bin.jar')
Use
javaaddpath('C:\full\path\to\mysql-connector-java-5.1.30-bin.jar')
If that is not the problem, lets skip the DriverManager (doesn't really help much) and see if the code below works, (or where it fails).
d = com.mysql.jdbc.Driver;
urlValid = d.acceptsURL('jdbc:mysql://localhost:3306/test'); %Should return true
props = java.util.Properties;
props.put('user','root'); props.put('password','1234');
con = d.connect('jdbc:mysql://localhost:3306/test',props)
The DriverManager construct doesn't really help much. It seems to be designed to allow a developer to load up a bunch of drivers, and then connect to any supported database without knowing or caring what the DB implementation was (e.g. Mysql, Postgresql, Oracle etc.) I have never seen this as a useful feature. I think (hope?) that this is being used less in favor of a DataSource construct.
Regardless, if this is your first time connecting Mysql to Matlab, you probably are best just directing using the provided Driver class.

"Data source name not found and no default driver"

java to mysql connection code:
Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
System.out.println("Driver loaded");
con = DriverManager.getConnection(url, "root", "sai");
stmt = con.createStatement();
System.out.println("Connection established");
after excution of above code
"Driver loaded" message printed on console but,
after that following exception is printed -
[Microsoft][ODBC Driver Manager]
Data source name not found and no default driver specified
i have already create DSN(MYSQL ODBC 3.51 Driver) for project
Please tell me solution of above problem.

"If somehow possible, don't use a JdbcOdbc driver, but a pure JDBC-Driver for your database!"
An example MySql pure JDBC-Driver would be the com.mysql.jdbc.Driver class found in the mysql-connector-java-5.x.x.jar file available for download from MySQL.
A good explanation of the differences between JDBC and JDBC-ODBC are available on wikipedia

If somehow possible, don't use a JdbcOdbc driver, but a pure JDBC-Driver for your database!
For the question of how to register the driver, from the javadocs for java.sql, Interface Driver:
It is strongly recommended that each
Driver class should be small and
standalone so that the Driver class
can be loaded and queried without
bringing in vast quantities of
supporting code.
When a Driver class is loaded, it
should create an instance of itself
and register it with the
DriverManager. This means that a user
can load and register a driver by
calling
Class.forName("foo.bah.Driver")
A separate call to 'newInstance' or registerDriver' is Cargo-Cult-programming.

It's a while since I've done this, but you could try to explicitly register your driver with the DriverManager class. This means that you're not depending upon something unseen implicitly happening in the background.
DriverManager.registerDriver((Driver)
Class.forName("sun.jdbc.odbc.JdbcOdbcDriver").newInstance());
con = DriverManager.getConnection(url, "root", "sai");
This will ensure that the "sun.jdbc.odbc.JdbcOdbcDriver" class is loaded and connected to the DriverManager.