and, this is from the same page as before.
http://technet.oracle.com/doc/server.815/a67781/c23cnsis.htm#2570
Oracle Isolation Levels
Oracle provides three transaction isolation levels:
read committed
This is the default transaction isolation level. Each
query executed by a transaction sees only data that
was committed before the query (not the transaction)
began. An Oracle query will never read dirty
(uncommitted) data.
Because Oracle does not prevent other transactions
from modifying the data read by a query, that data may
be changed by other transactions between two
executions of the query. Thus, a transaction that
executes a given query twice may experience both
nonrepeatable read and phantoms.
serializable transactions
Serializable transactions see only those changes that
were committed at the time the transaction began, plus
those changes made by the transaction itself through
INSERT, UPDATE, and DELETE statements. Serializable
transactions do not experience nonrepeatable reads or
phantoms.
read-only
Read-only transactions see only those changes that
were committed at the time the transaction began and
do not allow INSERT, UPDATE, and DELETE statements.
--- Jay Walters <[EMAIL PROTECTED]> wrote:
> Well I am hoping I am just confused and have
> misunderstood you.
>
> It appeared that you said JDBC connections and
> Sql*plus ones were different,
> and that a if I perform an insert inside a
> transaction using JDBC that
> within the same transaction I would not be able to
> read the row inserted.
>
> If in fact you did say that there are two things
> which are significant.
> First, the server does not distinguish by client
> type and both SQL*Plus and
> JDBC drivers look essentially the same to it. They
> both use the same wire
> protocol to speak with the server.
>
> On the second issue, read committed has to do with
> other transactions. Run
> the embedded JDBC program... you might need to fix
> up the connection URL.
>
> import java.sql.*; // JDBC classes
> public class Foo {
> public static void main( String[] args ) throws
> SQLException {
> // Get connection to the database
> DriverManager.registerDriver( new
> oracle.jdbc.driver.OracleDriver()
> );
> Connection con =
> DriverManager.getConnection(
> "jdbc:oracle:thin:@localhost:1521:ORCL", "scott",
> "tiger" );
>
> /* Create the table */
> Statement stmt = con.createStatement();
> stmt.execute( "CREATE TABLE FOO ( X
> VARCHAR2(32))" );
>
> con.setAutoCommit( false );
> stmt.executeUpdate( "INSERT INTO FOO VALUES
> ('Gina')" );
>
> /* Won't see Gina here! */
> ResultSet rs = stmt.executeQuery( "SELECT X FROM
> FOO" );
> System.out.println( "Gina says see nothing" );
> while( rs.next() ) {
> System.out.println( "Oh oh, Found " +
> rs.getString( 1 ));
> }
> rs.close();
>
> con.rollback();
>
> /* Won't see Gina here for sure! */
> rs = stmt.executeQuery( "SELECT X FROM FOO" );
> System.out.println( "Won't find anything here!" );
> while( rs.next() ) {
> System.out.println( "Found " + rs.getString( 1
> ));
> }
>
> /* All done, drop the table */
> stmt.execute( "DROP TABLE FOO" );
> }
> }
>
> _______________________________________________
> Jboss-development mailing list
> [EMAIL PROTECTED]
>
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