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3 tier architecture application or MVC application are different or same

Answer :- http://en.wikipedia.org/wiki/Multitier_architecture#Comparison_with_the_MVC_architecture Comparison with the MVC architecture At first glance, the three tiers may seem similar to the model-view-controller (MVC) concept; however, topologically they are different. A fundamental rule in a three tier architecture is the client tier never communicates directly with the data tier; in a three-tier model all communication must pass through the middle tier. Conceptually the three-tier architecture is linear. However, the MVC architecture is triangular: the view sends updates to the controller, the controller updates the model, and the view gets updated directly from the model. From a historical perspective the three-tier architecture concept emerged in the 1990s from observations of distributed systems (e.g., web applications) where the client, middle ware and data tiers ran on physically separate platforms. Whereas MVC comes from the previous decade (by work at Xerox PARC in th

How To Start, Stop and Restart Oracle Listener

Display Oracle Listener Status $ lsnrctl status LSNRCTL for Linux: Version 11.1.0.6.0 - Production on 04-APR-2009 16:27:39 Copyright (c) 1991, 2007, Oracle. All rights reserved. Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=192.168.1.2)(PORT=1521))) TNS-12541: TNS:no listener TNS-12560: TNS:protocol adapter error TNS-00511: No listener Linux Error: 111: Connection refused Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=IPC)(KEY=EXTPROC))) TNS-12541: TNS:no listener TNS-12560: TNS:protocol adapter error TNS-00511: No listener Linux Error: 2: No such file or directory If the Oracle listener is running, you’ll get the following message. $ lsnrctl status LSNRCTL for Linux: Version 11.1.0.6.0 - Production on 04-APR-2009 16:27:02 Copyright (c) 1991, 2007, Oracle. All rights reserved. Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=192.168.1.2)(PORT=1521))) STATUS of the LISTENER ------------------------ Alias L

SQL> startup error

[oracle@localhost ~]$ sqlplus sys as sysdba SQL*Plus: Release 11.2.0.1.0 Production on Tue Feb 15 16:09:03 2011 Copyright (c) 1982, 2009, Oracle. All rights reserved. Enter password: Connected to an idle instance. SQL> selct * from v$version SP2-0734: unknown command beginning "selct * fr..." - rest of line ignored. SQL> select * from v$version; select * from v$version * ERROR at line 1: ORA-01034: ORACLE not available Process ID: 0 Session ID: 0 Serial number: 0 SQL> startup ORA-01078: failure in processing system parameters LRM-00109: could not open parameter file '/u01/app/oracle/product/11.2.0/db_1/dbs/initDB11G.ora'

How do I download and install Java for my Linux computer?

1) Change the permission of the file you downloaded to be executable. Type: chmod a+x jre-6u -linux-i586.bin 2) Verify that you have permission to execute the file. Type: ls -l 3) Change to the directory in which you want to install. Type: cd For example, to install the software in the /usr/java/ directory, Type: cd /usr/java/ 4) Run the self-extracting binary Type: ./jre-6u -linux-i586.bin 5) Verify that the jre1.6.0_ sub-directory is listed under the current directory.

java.lang.ClassCastException: com.sun.xml.internal.messaging.saaj.soap.ver1_1.Envelope1_1Impl cannot be cast to org.apache.axis.message

FIRST SOLUTION: (for administrators; is a global solution) Set the system property when invoking Java process : -Djavax.xml.soap.MessageFactory=org.apache.axis.soap.MessageFactoryImpl SECOND SOLUTION: (for developers; is a local solution) a ) Locate in the source code of your application the place where de message factory is instantied to create SOAP messages: MessageFactory.newInstance() // --> javax.xml.soap.MessageFactory b) Replace this expression (MessageFactory.newInstance()) with: new org.apache.axis.soap.MessageFactoryImpl()

To get the last time when table was updated

select scn_to_timestamp(max(ora_rowscn)) from OWNER.TABLE_NAME while running above query you can have error:- ERROR at line 1: ORA-08181: specified number is not a valid system change number ORA-06512: at "SYS.SCN_TO_TIMESTAMP", line 1 Cause: supplied scn was beyond the bounds of a valid scn. Action: use a valid scn. reason behind this can be:- This only works as long as the snapshot is still around. After that, it appears to go into a frozen state. All off my records older than a certain point have the same SCN. you can also use:- SELECT * FROM all_tab_modifications