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Java prepared statement get generated keys do not work in DB2 but work in mySQL?

I have a very simple table that is in both MySQL and DB2 called STUDENT. The columns are: ID (primary key, auto incrementing), FIRST_NAME, LAST_NAME, AGE.
The table is replicated in both databases, so they should be the same syntactically. However, I have spent the entire day trying to figure out why, when I write a simple Java program to insert into the database, the MySQL version returns back the generated key via PreparedStatement.getGeneratedKeys(), while the DB2 version does not return anything.
My code looks like:
String sql = "INSERT INTO STUDENT (FIRST_NAME, LAST_NAME, AGE) VALUES ('Jacob', 'Eldy', 19)"
final Connection connection = getConnection(dataSource.get());
int[] insertedRows = null;
ResultSet rs = null;
PreparedStatement ps = null;
try {
ps = connection.prepareStatement(sql, Statement.RETURN_GENERATED_KEYS);
ps.addBatch();
insertedRows = ps.executeBatch();
rs = ps.getGeneratedKeys();
while(rs.next()) {
LOGGER.info(rs.getString(1));
}
connection.commit();
} catch (Exception e) {
try {
connection.rollback();
} catch (SQLException e) {
e.printStackTrace();
}
} finally {
close(ps, connection);
}
After committing the connection for both databases DB2 and MySQL, both actually show the row being inserted, and the more I insert, a new row appears with an auto incremented ID, however only the MySQL database has a value in while(rs.next()), the DB2 version just skips over it since it is empty.
Am I doing something wrong? Is this just an incompatibility issue with DB2 and it just does not return the generated value? If so, what would be the best solution for tackling this issue?
UPDATE, adding the two DDLs for DB2 & mySQL:
mySQL DDL:
CREATE TABLE 'STUDENT'
...
`ID` int NOT NULL AUTO_INCREMENT
PRIMARY KEY('ID')
AUTO_INCREMENT=19073
DB2 DDL:
CREATE TABLE STUDENT
(
ID INTEGER DEFAULT IDENTITY GENERATED ALWAYS NOT NULL
PRIMARY KEY (ID)
)

CREATE TABLE STUDENT
(
ID INT NOT NULL GENERATED BY DEFAULT AS IDENTITY PRIMARY KEY
, FIRST_NAME VARCHAR (20)
, LAST_NAME VARCHAR (20)
, AGE SMALLINT
);
The following code based on the Making batch updates in JDBC applications links (this one is for Db2 for LUW) provided by others works as expected with the table definition above:
PreparedStatement ps = con.prepareStatement
(
"INSERT INTO STUDENT (FIRST_NAME, LAST_NAME, AGE) " +
"VALUES (?,?,?)"
, Statement.RETURN_GENERATED_KEYS
);
ps.setString (1, "Jacob");
ps.setString (2, "Eldy");
ps.setShort (3, (short) 19);
ps.addBatch();
ps.setString (1, "Jacob");
ps.setString (2, "Eldy");
ps.setShort (3, (short) 19);
ps.addBatch();
int [] numUpdates = ps.executeBatch();
for (int i=0; i < numUpdates.length; i++)
if (numUpdates[i] == Statement.SUCCESS_NO_INFO)
System.out.println("Execution " + i + ": unknown number of rows updated");
else
System.out.println("Execution " + i + " successful: " + numUpdates[i] + " rows updated");
ResultSet[] resultList = ((com.ibm.db2.jcc.DB2PreparedStatement) ps).getDBGeneratedKeys();
if (resultList.length != 0)
for (int i = 0; i < resultList.length; i++)
{
while (resultList[i].next())
System.out.println("Automatically generated key value = " + resultList[i].getBigDecimal(1));
resultList[i].close();
}
else
System.out.println("Error retrieving automatically generated keys");

Am I doing something wrong? Is this just an incompatibility issue with DB2 and it just does not return the generated value? If so, what would be the best solution for tackling this issue?
Yes, you are doing wrong. It's not incompatibility issue, and it's not an issue. DB2 is different than MySQL. You can't handle both because you have incompatible DDL. Since no records are inserted into DB2 the value of the key is not available.
The solution to the issue is to create a trigger on insert a record to make sure the primary key is inserted into DB. If you are missing a key then select it from the sequence and substitute the value.
Now if identity is generated into DB2 like this
CREATE TABLE STUDENT
(
ID INTEGER DEFAULT IDENTITY GENERATED ALWAYS NOT NULL
PRIMARY KEY (ID)
)
So it will always return getGeneratedKeys().

Prepared Statement Primary Key store seed 1 and increment

Okay, so I just started JDBC with derby client and I'm kind of new with it.
I set column ID as primary key with int as it's data type. However, I'm not sure if I should include myStatement.setString(1, ?); because I thought it should Auto Increment but it looks like it's not doing it.
Here's my Grab file details:
create table "ADMIN1".STUDENTPERSONALDETAILS
(
ID INTEGER not null primary key,
STUDENTID VARCHAR(10) not null,
LASTNAME VARCHAR(50) not null,
FIRSTNAME VARCHAR(50) not null,
MIDDLENAME VARCHAR(50) not null,
PLACEOFBIRTH VARCHAR(200) not null,
DOB VARCHAR(50) not null,
GENDER VARCHAR(4) not null,
CIVILSTATUS VARCHAR(7) not null,
RELIGION VARCHAR(15) not null,
NATIONALITY VARCHAR(20) not null
)
How can I correct my PreparedStatement or My Table in such a way that adding of value for column ID will be automatic so that I can start setString(2, studentID) and avoid getting error about the number of columns not matching with what was supplied?
Here's my code:
addButton.addActionListener(new ActionListener () {
#Override
public void actionPerformed(ActionEvent e) {
try {
String myDbUrl = "jdbc:derby://localhost:1527/Enrollment"; //stores url to string
String userName = "admin1";
String Password = "admin1";
Connection myDBConnection = DriverManager.getConnection(myDbUrl, userName, Password);
String myQuery = "INSERT INTO STUDENTPERSONALDETAILS"
+ "(STUDENTID,LASTNAME,FIRSTNAME,MIDDLENAME,PLACEOFBIRTH,DOB,GENDER,CIVILSTATUS,RELIGION,NATIONALITY) "
+ "VALUES(?,?,?,?,?,?,?,?,?,?) ";
String adminissionNo ;
String studentID = tfStudentId.getText().toString();
String lastName = tfLastName.getText().toString();
String firstName = tfFirstName.getText().toString();
String middleName = tfMiddleName.getText().toString();
String placeOfBirth = tfPob.getText().toString();
String dateOfBirth = listDOB.getSelectedItem().toString();
String gender = listGender.getSelectedItem().toString();
String civilStatus = listCivilStatus.getSelectedItem().toString();
String religion = listReligion.getSelectedItem().toString();
String nationality = listNationality.getSelectedItem().toString();
PreparedStatement myStatement = myDBConnection.prepareStatement(myQuery);
myStatement.setString(2, lastName);
myStatement.setString(3, firstName);
myStatement.setString(4, middleName);
myStatement.setString(5, placeOfBirth);
myStatement.setString(6, dateOfBirth);
myStatement.setString(7, gender);
myStatement.setString(8, civilStatus);
myStatement.setString(9, religion);
myStatement.setString(10, nationality);
boolean insertResult = myStatement.execute();
if(insertResult == true)
JOptionPane.showMessageDialog(null, "Successfully Added Information");
else
JOptionPane.showMessageDialog(null, "Encountered an error while inserting data");
}
catch(SQLException ex) {
JOptionPane.showMessageDialog(null, ex.toString());
}
}
});
Is it necessary to include myStatement.setString(1, integervaluehere) for Primary Keys? Isn't it supposed to autoincrement?
I'd appreciate any explanation because I just started learning the basics of PreparedStatements recently.
I tried counting the columns and tried 10 and 11 lines of myStatement.setString(), but still can't get it to insert data because of mismatch.
Thanks in advance.

You need to mention 'auto increment' explicitly.
Or you can write your own java code to track the Id for each table and whenever you ask the method to give the ID it will return lastID + 1.
But, I think now you can go with auto_increment option.

If you want it to autoincrement you need to say so in the column definition, and you haven't.
I don't know what 'default 1' in your title is supposed to mean, as you haven't mentioned it in your question, but you can't have a default value and autoincrement. It doesn't make sense.
I don't know what 'store seed 1' means either, in your edit.
When you have a column with a default value you want to rely on, or autoincrement, you don't mention it at all in the INSERT statement, so there is no positional argument to set.

First, set the primary identifier column to autoincrement. Since your query already excludes the primary key, you then only have to change the PreparedStatement indexes to match the number of parameters in your query starting from one.
Since you have 10 columns in addition to the primary ID column, your PreparedStatement might look something like the following:
PreparedStatement myStatement = myDBConnection.prepareStatement(myQuery);
myStatement.setString(1, studentId);
myStatement.setString(2, lastName);
myStatement.setString(3, firstName);
myStatement.setString(4, middleName);
myStatement.setString(5, placeOfBirth);
myStatement.setString(6, dateOfBirth);
myStatement.setString(7, gender);
myStatement.setString(8, civilStatus);
myStatement.setString(9, religion);
myStatement.setString(10, nationality);
Note that you do not need to have the instruction, myStatement.setInt(1, primaryId);, once you have changed the primary key in your table to auto-increment. However, if you elect to keep the primary key as non-autoincrementing, then you must explicitly specify the primary key value and provide a parameter in your query to insert that data.

If you're using MySQL Workbench, which if you're not, I highly recommend because it just works. You have to choose Auto-Increment as a characteristic of that column. If you want your column to auto increment, when creating columns in your database, check the option Auto-Increment, sometimes written as AI.

Java PreparedStatement and ON DUPLICATE KEY UPDATE: how do I know whether row was inserted or updated?

Having following code, how do I know if the execute() method resulted in insert or in update?:
Connection c = DriverManager.getConnection(connectionString);
PreparedStatement st = c.prepareStatement("INSERT INTO `table`(`field1`) VALUES (?) ON DUPLICATE KEY UPDATE id=LAST_INSERT_ID(id);");
st.setString(1,"some value");
st.execute();
Thanks in advance.

Consider the following MySQL test table:
CREATE TABLE `customers` (
`id` int(11) NOT NULL AUTO_INCREMENT,
`name` varchar(100) NOT NULL,
`email` varchar(100) NOT NULL,
PRIMARY KEY (`id`),
UNIQUE KEY `email` (`email`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8 AUTO_INCREMENT=1 ;
with existing sample data as follows:
id name email
-- -------------- ----------------
1 Loblaw, Bob bob#example.com
2 Thompson, Gord gord#example.com
With the default connection setting compensateOnDuplicateKeyUpdateCounts=false (described here) the following Java code
PreparedStatement ps = dbConnection.prepareStatement(
"INSERT INTO customers (name, email) " +
"VALUES (?, ?) " +
"ON DUPLICATE KEY UPDATE " +
"name = VALUES(name), " +
"id = LAST_INSERT_ID(id)");
ps.setString(1, "McMack, Mike");
ps.setString(2, "mike#example.com");
int euReturnValue = ps.executeUpdate();
System.out.printf("executeUpdate returned %d%n", euReturnValue);
Statement s = dbConnection.createStatement();
ResultSet rs = s.executeQuery("SELECT LAST_INSERT_ID() AS n");
rs.next();
int affectedId = rs.getInt(1);
if (euReturnValue == 1) {
System.out.printf(" => A new row was inserted: id=%d%n", affectedId);
}
else {
System.out.printf(" => An existing row was updated: id=%d%n", affectedId);
}
produces the following console output
executeUpdate returned 1
=> A new row was inserted: id=3
Now run the same code again with the parameter values
ps.setString(1, "Loblaw, Robert");
ps.setString(2, "bob#example.com");
and the console output is
executeUpdate returned 2
=> An existing row was updated: id=1
This demonstrates that .executeUpdate really can return 2 if the unique index causes an existing row to be updated. If you require further assistance with your actual test code then you should edit your question to include it.
Edit
Further testing reveals that .executeUpdate will return 1 if
the attempted INSERT is aborted because it would result in a duplicate UNIQUE key value, and
the specified ON DUPLICATE KEY UPDATE changes do not actually modify any values in the existing row.
This can be confirmed by running the above test code twice in a row with the exact same parameter values. Note that the UPDATE ... id = LAST_INSERT_ID(id) "trick" does ensure that the correct id value is returned.
That probably explains OP's test results if the only value being inserted was the UNIQUE key value.

Use executeUpdate instead as it returns an int row count.
UPDATE 1: According to the MySQL INSERT ... ON DUPLICATE KEY UPDATE documentation:
With ON DUPLICATE KEY UPDATE, the affected-rows value per row is 1 if
the row is inserted as a new row, and 2 if an existing row is updated.
UPDATE 2: INSERT IGNORE may also be an option:
INSERT IGNORE INTO `table`(`field1`) VALUES (?)
executeUpdate should return 1 when a new row is inserted and 0 when there is a duplicate.

How to avoid inserting null values into Primary key or Not Null columns?

I am inserting into a table from my jdbc program,
like this
PreparedStatement ps = con.prepareStatement(sqlqry);
ps.setInt(1,dto.getInstall_id());
ps.setString(2, dto.getDashboard_name());
ps.setString(3, dto.getDashboard_type());
ps.setString(4, dto.getDashboard_image());
But in the table i have column say D_ID which in is primary key and i dont want o insert the D_ID from my program into table because the same id might be already exist. So for avoiding the PK_CONSTRAINT I am not inseting it.
But when i try this i am getting this error.
ORA-01400: cannot insert NULL into ("TESTDB"."TESTATBLE"."D_ID")
So how can i solve this problem, Any alternative like if i insert D_ID from the program my JDBC program the D_ID column should dynamically generate id's in the table.
I am banging my head for this. Please help!

You should create that ID using a sequence. So for each ID column that you have, you create a corresponding sequence:
create table testatble
(
d_id integer not null primary key,
install_id integer not null,
dashboard_name varchar(100)
... more columns ....
);
create sequence seq_testatble_d_id;
You can use it like this:
// note that there is no placeholder for the D_ID column
// the value is taken directly from the sequence
String sqlqry =
"insert into testatble (d_id, install_id, dashboard_name) " +
"values (seq_testatble_d_id.nextval, ?, ?)";
PreparedStatement ps = con.prepareStatement(sqlqry);
ps.setInt(1,dto.getInstall_id());
ps.setString(2, dto.getDashboard_name());
... more parameters ...
ps.executeUpdate();
That way the id will be generated automatically.
If you need the generated ID in your Java code after the insert, you can use getGeneratedKeys() to return it:
// the second parameter tells the driver
// that you want the generated value for the column D_ID
PreparedStatement ps = con.prepareStatement(sqlqry, new String[]{"D_ID"});
// as before
ps.setInt(1,dto.getInstall_id());
ps.setString(2, dto.getDashboard_name());
... more parameters ...
ps.executeUpdate();
// now retrieve the generated ID
int d_id = -1;
ResultSet rs = ps.getGeneratedKeys();
if (rs.next()) // important!
{
d_id = rs.getInt(1);
}
rs.close();
More on sequences in the Oracle manual: http://docs.oracle.com/cd/E11882_01/server.112/e26088/pseudocolumns002.htm#SQLRF00253

You should use Auto Increment number for ID(I Oracle you can use sequence). You can do this at the link:
Create ID with auto increment on oracle
You should also read this. If there is a sequence to your ID then here you can read information about that.

Mysql inserts the data as unknown values java

Hello i am using prepared statement to insert the values into mysql.
I am facing an issue in an string which is inserting as "c2a054656e6e6973c2a0" for value " Tennis " and i tried to use trim to trim the whitespace in front of the "Tennis" it did not work .From this question Why trim is not working? i tried using the solution poNumber.replace(String.valueOf((char) 160), " ").trim(); and it worked. can any one give solution for this?
SAMPLE CODE
CREATE TABLE `news1` (
`article_id` int(11) NOT NULL AUTO_INCREMENT,
`article_title` varchar(500) COLLATE utf8_bin NOT NULL,
`article_subcategory` varchar(255) COLLATE utf8_bin DEFAULT NULL,
PRIMARY KEY (`article_id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8 COLLATE=utf8_bin AUTO_INCREMENT=22 ;
//Sample category will be "Home » Tennis"
String category = item.getArticle_category();
String categoryArray[] = category.split("»");
preparedStatement = connect
.prepareStatement("INSERT INTO news1 VALUES(default,?,?)");
System.out.println(categoryArray[2].replace(String.valueOf((char) 160), " ")
.trim());
preparedStatement.setString(1, item.getArticle_title());
preparedStatement.setString(2, categoryArray[2]);

you are doing this categoryArray[2].replace(String.valueOf((char) 160), " ") .trim() in sys out but you do preparedStatement.setString(2, categoryArray[2]); in your statement
String temp = categoryArray[2].replace(String.valueOf((char) 160), " ") .trim();
System.out.println(temp);
and use temp in
preparedStatement.setString(2, temp);