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How to update updateble ResultSet with SQL Function e.g. NOW()

Is there any way to call SQL Function during updateXXX method in ResultSet of type ResultSet.TYPE_FORWARD_ONLY, ResultSet.CONCUR_UPDATABLE.
For example look at this code fragment:
stmt = con.createStatement(ResultSet.TYPE_FORWARD_ONLY, ResultSet.CONCUR_UPDATABLE);
rs = stmt.executeQuery(query);
while (rs.next()) {
rs.updateTimestamp("status_time", "NOW()"); // call some SQL function during update
rs.updateRow();
}
Is there any way to update value such way? The above example ofcourse don't work.

You can't do that. These methods are for setting actual values, not for executing SQL functions.

Getting a result back from a stored procedure in Java

I am having the hardest time calling an Oracle stored procedure from a java runtime environment. The stored procedure that I am calling has 2 parameters 1 in and 1 out. Here is how I call the stored procedure... How do you get the resultSet from an Oracle ref_cursor
ds = (DataSource)initialContext.lookup("JDBC/EPCD13DB");
conn = ds.getConnection();
callableStatement = conn.prepareCall(storedProcCall);
callableStatement.setString(1, input1);
callableStatement.registerOutParameter(2, OracleTypes.CURSOR);
callableStatement.execute();//(ResultSet) callableStatement.getObject(1);
ResultSet rs = callableStatement.getResultSet();
while(rs.next()){
Provider tempProv = new Provider();
tempProv.setResourceId(rs.getLong("res_id"));
tempProv.setFirstName(rs.getString("First_Name"));
tempProv.setLastName(rs.getString("Last_Name"));
tempProv.setMiddleName(rs.getString("Middle_Name"));
ObjList.add(tempProv);
}
rs.close();

You should be able to retrieve the ResultSet with:
ResultSet rSet = (ResultSet)callableStatement.getObject(2);

Does this help you? Seems like you have to call getObject and cast it into a result set before querying on the result set.
Credit:: http://www.mkyong.com/jdbc/jdbc-callablestatement-stored-procedure-cursor-example/

I believe it returns only one output(oracle cursor)
ResultSet rs=(ResultSet) callableStatement.getObject(2);
and then iterate your cursor result set for records inside:
while(rs.next()){
Provider tempProv = new Provider();
tempProv.setResourceId(rs.getLong("res_id"));
tempProv.setFirstName(rs.getString("First_Name"));
tempProv.setLastName(rs.getString("Last_Name"));
tempProv.setMiddleName(rs.getString("Middle_Name"));
ObjList.add(tempProv);
}

In spring framework fetching database cursor results can be easily achieved. It has inbuilt classes like maprow, storedprocedure to serve the purpose. PFB the link
http://static.springsource.org/spring/docs/3.1.x/spring-framework-reference/html/jdbc.html#jdbc-simple-jdbc-call-1

How to get query plan information from Postgres into JDBC

I want to capture the cost numbers from the query plan you get when you 'Explain' a query. Is there any way to get at this data inside of a Java ResultSet(or similar object)?

Sure, just run it as a regular statement:
Statement stmt = connection.createStatement();
ResultSet rs = stmt.executeQuery("explain analyze select * from foo");
while (rs.next())
{
System.out.println(rs.getString(1));
}

In addition to the answer supplied above, I would suggest that you make use of the ability to format EXPLAIN plans as XML in PostgreSQL 9.0 and later.
EXPLAIN ( analyze on, format xml ) SELECT ...
This will give you explain output you can more easily work with in Java by manipulating it as XML.

An other example with PreparedStatement, this time.
Like this:
PreparedStatement preparedStatement = connection.prepareStatement("EXPLAIN (ANALYZE true , VERBOSE true , BUFFERS true)" +
"SELECT * FROM Table");
ResultSet resultSet = preparedStatement.executeQuery();
while (resultSet.next()) {
System.out.println(resultSet.getString(1));
}
Or with a bind parameter:
PreparedStatement preparedStatement = connection.prepareStatement("EXPLAIN (ANALYZE true , VERBOSE true , BUFFERS true)" +
"SELECT * FROM Player WHERE id = ?");
preparedStatement.setLong(1, 1);
ResultSet resultSet = preparedStatement.executeQuery();
while (resultSet.next()) {
System.out.println(resultSet.getString(1));
}

Is there a way to retrieve the autoincrement ID from a prepared statement

Is there a way to retrieve the auto generated key from a DB query when using a java query with prepared statements.
For example, I know AutoGeneratedKeys can work as follows.
stmt = conn.createStatement();
stmt.executeUpdate(sql, Statement.RETURN_GENERATED_KEYS);
if(returnLastInsertId) {
ResultSet rs = stmt.getGeneratedKeys();
rs.next();
auto_id = rs.getInt(1);
}
However. What if I want to do an insert with a prepared Statement.
String sql = "INSERT INTO table (column1, column2) values(?, ?)";
stmt = conn.prepareStatement(sql);
//this is an error
stmt.executeUpdate(Statement.RETURN_GENERATED_KEYS);
if(returnLastInsertId) {
//this is an error since the above is an error
ResultSet rs = stmt.getGeneratedKeys();
rs.next();
auto_id = rs.getInt(1);
}
Is there a way to do this that I don't know about. It seems from the javadoc that PreparedStatements can't return the Auto Generated ID.

Yes. See here. Section 7.1.9. Change your code to:
String sql = "INSERT INTO table (column1, column2) values(?, ?)";
stmt = conn.prepareStatement(sql, Statement.RETURN_GENERATED_KEYS);
stmt.executeUpdate();
if(returnLastInsertId) {
ResultSet rs = stmt.getGeneratedKeys();
rs.next();
auto_id = rs.getInt(1);
}

There's a couple of ways, and it seems different jdbc drivers handles things a bit different, or not at all in some cases(some will only give you autogenerated primary keys, not other columns) but the basic forms are
stmt = conn.prepareStatement(sql, Statement.RETURN_GENERATED_KEYS);
Or use this form:
String autogenColumns[] = {"column1","column2"};
stmt = conn.prepareStatement(sql, autogenColumns)

Yes, There is a way. I just found this hiding in the java doc.
They way is to pass the AutoGeneratedKeys id as follows
String sql = "INSERT INTO table (column1, column2) values(?, ?)";
stmt = conn.prepareStatement(sql, Statement.RETURN_GENERATED_KEYS);

I'm one of those that surfed through a few threads looking for solution of this issue ... and finally get it to work. FOR THOSE USING jdbc:oracle:thin: with ojdbc6.jar PLEASE TAKE NOTE:
You can use either methods:
(Method 1)
Try{
String yourSQL="insert into Table1(Id,Col2,Col3) values(SEQ.nextval,?,?)";
myPrepStatement = <Connection>.prepareStatement(yourSQL, Statement.RETURN_GENERATED_KEYS);
myPrepStatement.setInt(1, 123);
myPrepStatement.setInt(2, 123);
myPrepStatement.executeUpdate();
ResultSet rs = getGeneratedKeys;
if(rs.next()) {
java.sql.RowId rid=rs.getRowId(1);
//what you get is only a RowId ref, try make use of it anyway U could think of
System.out.println(rid);
}
} catch (SQLException e) {
//
}
(Method 2)
Try{
String yourSQL="insert into Table1(Id,Col2,Col3) values(SEQ.nextval,?,?)";
//IMPORTANT: here's where other threads don tell U, you need to list ALL cols
//mentioned in your query in the array
myPrepStatement = <Connection>.prepareStatement(yourSQL, new String[]{"Id","Col2","Col3"});
myPrepStatement.setInt(1, 123);
myPrepStatement.setInt(2, 123);
myPrepStatement.executeUpdate();
ResultSet rs = getGeneratedKeys;
if(rs.next()) {
//In this exp, the autoKey val is in 1st col
int id=rs.getLong(1);
//now this's a real value of col Id
System.out.println(id);
}
} catch (SQLException e) {
//
}
Basically, try not used Method1 if you just want the value of SEQ.Nextval, b'cse it just return the RowID ref that you may cracked your head finding way to make use of it, which also don fit all data type you tried casting it to! This may works fine (return actual val) in MySQL, DB2 but not in Oracle.
AND, turn off your SQL Developer, Toad or any client which use the same login session to do INSERT when you're debugging. It MAY not affect you every time (debugging call) ... until you find your apps freeze without exception for some time. Yes ... halt without exception!

Connection connection=null;
int generatedkey=0;
PreparedStatement pstmt=connection.prepareStatement("Your insert query");
ResultSet rs=pstmt.getGeneratedKeys();
if (rs.next()) {
generatedkey=rs.getInt(1);
System.out.println("Auto Generated Primary Key " + generatedkey);
}

What is the equivalent of Oracle’s REF CURSOR in MySQL when using JDBC?

In Oracle I can declare a reference cursor...
TYPE t_spool IS REF CURSOR RETURN spool%ROWTYPE;
...and use it to pass a cursor as the return value...
FUNCTION end_spool
RETURN t_spool
AS
v_spool t_spool;
BEGIN
COMMIT;
OPEN v_spool FOR
SELECT
*
FROM
spool
WHERE
key = g_spool_key
ORDER BY
seq;
RETURN v_spool;
END end_spool;
...and then capture it as a result set using JDBC...
private Connection conn;
private CallableStatement stmt;
private OracleResultSet rset;
[...clip...]
stmt = conn.prepareCall("{ ? = call " + call + "}");
stmt.registerOutParameter(1, OracleTypes.CURSOR);
stmt.execute();
rset = (OracleResultSet)stmt.getObject(1);
What is the equivalent in MySQL?

Mysql has an implicit cursor that you can magically return from a stored procedure if you issue a select.
Here's an example:
CREATE PROCEDURE `TEST`()
MODIFIES SQL DATA
BEGIN
SELECT * FROM test_table;
END;
and in your java code:
String query = "{CALL TEST()}";
CallableStatement cs = con.prepareCall(query,
ResultSet.TYPE_SCROLL_INSENSITIVE,
ResultSet.CONCUR_READ_ONLY);
ResultSet rs = cs.executeQuery();

Googling on cursors in MySQL, it doesn't seem like you can actually return a Cursor from a Proc or Function. Additionally, I found the following in the MySQL JDBC manual:
"MySQL does not support SQL cursors, and the JDBC driver doesn't emulate them, so "setCursorName()" has no effect."
In general, I believe Oracle's implementation here breaks JDBC, and is not used elsewhere (MySQL, MSSQL, etc). You should be returning your results as a select statement and iterating over the JDBC ResultSet, as is standard (and intended) practice when using JDBC.

fill a temporary table in a procedure and just read the temporary table... :)