I think that first thing beginner ADF developer gets familiar with is bussiness components (BC) and in particular View Objects. Thats the base and main axis of ADF BC. Most common usage is definately Entity or SQL Query based View Objects. But when facing a real world requirements, its not as rare case to build BC on some different kind…
Author: Danas Tarnauskas
REST with hierarchical (tree) data query and response payload
Probably everyone using REST webservices face requirements which makes you deal with hierarchical (tree) data structures. How to clearly define when data is expected to be returned in a hierarchical structure and when just a flat object? And what if you need different hierarchical responses in different use cases for the same REST resource? Here I’m going to tell you…
How to get LOV value instead of index when it is used in standalone ADF “selectOneChoice” component ?
Its a common issue in ADF to get a LOV value instead of index in ADF form. How to do that in collection context, for example – when we have “selectOneChoice” in table row cell, I’ve noted in another post. And that was really easy. Its more complicated when we need the same in “selectOneChoice” used in form, standalone component…
Get “ORA-56901: non-constant expression is not allowed for pivot|unpivot values” ? Not a big deal, check a workaround!
Problem Get “ORA-56901: non-constant expression is not allowed for pivot|unpivot values” while trying to execute SQL statement with pivot clause. Lets consider this tiny sample: Here is the table: SQL statement with PIVOT clause and constant expressions, which executes successfully: SQL statement with PIVOT clause and dynamic expressions, which fails: Solution Workaround – just don’t use PIVOT at this…
ADF application layout messed up after migration to 12.2.1 … What might be the reason ?
Problem: After migration of ADF application from 12.1.3 to 12.2.1 layout was messed up. In particular – component stretching was disordered. Reason: As ADF is going step by step to adaptive layouting, component stretching is optimized accordingly. In version 11.1.1.7 new context parameter was introduced: oracle.adf.view.rich.geometry.DEFAULT_DIMENSIONS. It basically tells what dimensions for stretchable components should be applied by default. For example…
JBO-26041: Failed to post data to database during “Update”… What might be the reason?
Problem: Exception during data save is thrown: oracle.jbo.DMLException: JBO-26041: Failed to post data to database during “Update”: SQL Statement “UPDATE… It might be followed by similar to this one: java.sql.SQLException: Fail to construct descriptor: Unable to resolve type “NVARCHAR2″… Solution: Check if SQLType attribute of an entity/view object attribute being updated is correct. For example it can be set to…
Override inputListOfValues component model and Continuous Query Notification sample in ADF
Requirement: Standard ADF inputListOfValues component should behave like this: When pressed “Search”, action should stop and wait untill any change happen in DB table being searched When change happen in DB table, search should resume among updated data. If no change happen it should resume after 10 seconds timeout In addition – search input field validation should happen on “Search”…
WebSocket together with DB Change Notification in ADF for immediate data refresh in browser (complete sample).
Requirement We have DB table contents displayed in ADF GUI After changes in that DB table (by anyone else in the background) we want to immediately display in our currenlty open browser session Solution To achieve our goal we need somehow to know when changes in DB happen. Once we know when, need to notify browser session in order it…
How to select all JDBC Database Change Notification Registrations and clean them?
Question: How do I select all database change notifications registered via JDBC driver by my DB user? Answer: select * from user_change_notification_regs Question: How do I clean all of my DB change notifications? Answer: Database change notifications registered via JDBC driver can be deregistered only the same way – using JDBC driver. Therefore you need to execute this code: This…
How to add ADF source code in JDeveloper 12c ?
Problem I want to have ADF source code available in my project. Solution Open service request ticket at My Oracle Support and ask to provide you a source code for ADF. Oracle staff will provide you a security code and a link to download a zip file. Open JDeveloper, select Tools -> Manage Libraries… Click Libraries tab Select folder User…