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Is there a way to uniquely identify a column via jdbc? I do not mean via schema table column

I am trying to track changes made to a database (schema) using a java app. We are trying to track changes for each column/unique-constraint/index and table.
Functionally I know table.column is unique. So, if the datatype of a column changes, we know which column to find and record the change. But what if the name changes? If JDBC's result set is ordered (it asks for index), then I can rely on the order to give me the same column everytime, even if the name changes. Will there be any surprises here, since it is a result 'set'?
However, I learnt that we can change the order of the columns as well. Isn't there any unique ID associated with the columns so that they can be picked up on that basis?
I would mostly not want to use information_schema route, but even though i checked there for mysql, found nothing useful.

How Can I get table's primary key via Oracle Database Change Notification

I could get notifications from an Oracle database thanks to this code and omitting this line:
prop.setProperty(OracleConnection.DCN_QUERY_CHANGE_NOTIFICATION,"true");
Also I could solve my ORA-29977 problem changing select * from act_code_metadata where product_id=1159 with select column_with_Number_type from act_code_metadata where product_id=1159
Everything works as expected :D
This is the code I use to print the row's information (Java 8):
DatabaseChangeRegistration dcp.addListener((DatabaseChangeEvent dce) ->
System.out.println(
"Changed row id : " +
dce.getTableChangeDescription()[0].getRowChangeDescription()[0].getRowid().stringValue()
+ " " + dce.getTableChangeDescription()[0].getRowChangeDescription()[0].getRowOperation().toString()));
But all the information I get is the row's physical address (rowid) and the operation involved (insert, delete or update).
I need to identify the row being modified/inserted/deleted to refresh my cached data in several Swing controls in my GUI.
I've read that, despite the rowid being imutable, the same rowid can be re-assigned if the row is deleted and a new one is inserted, and the rowid can change if the row is in a partitioned table. So the best that can be done is using the rowid and the row's primary key.
My table has a autoincrementable primary key (with a sequence and a trigger) created with this code.
I have no control on what happens on the database or if somebody inserts and deletes rows several times. So I can get the wrong row when selecting it using the rowid given by the notification.
Is there a way that I can get my row's primary key via Oracle Database Change Notification so I can identify the inserted/deleted/modified row correctly?
I'm working with Oracle Database XE 11.2 Express and Java 8. The user for database connection already has the change notification privilege.

It seems that you have a lot of overhead trying to basically maintain a fresh snapshot of the data in your GUI. It may be simpler to look at client result caching and just re-running your query every X seconds; and let Oracle do the magic of seeing if the data changed. You would be limited to a JDBC driver that supports OCI. See http://docs.oracle.com/cd/E11882_01/server.112/e41573/memory.htm#PFGRF985 for details. With client result caching, the first time the SQL is executed, it will take say 500 milliseconds. Next query using the same criteria it will take 2 or 3 milliseconds. Assuming the result set is small (less than 100 rows is quite small), you can get a lot better results without all that framework you are trying to build.

update multiple row with a query in mysql using java

Helo,
I am a beginner java programmer.
I need to update multiple rows with a query using mysql database and java codes.
I need to update the age field (data type int) in the database based on the current date. I believe I need to iterate and use the hasnext ... but I just unable.

If you need to update all the rows using a common logic based on current date, write a single update query and execute it. It will update all the rows. If logic is different then use updatble result set.

Are you facing a problem in executing an update query or is it with the iteration on integer array. Please provide more details. And if you are attempting to update similar data, try doing it using a single query, as executing queries in loop is not recommended.

java/mysql how to get changed data

I'm working on a Java program that is connected to a MySQL database. One of the things that I want to do is show if/what data change to a current table has been made. Any ideas?

Retrieve the value of the newly inserted row in sql server

I am developing android application. In my application i have used sql server2008 R2. I am inserting the row in the sql server on some click event. Now i want to fetch the first column's value from the newly inserted row. The first column's value of that schema is auto generated.I am inserting the value from the second column in my insert query. I am using jdbc. In .net to achieve this functionality method ExecuteScalar() is der. But what in java. I have done lots of googling but haven't found any thing. Help me if you the solution.

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How to get the insert ID in JDBC?