Forms inserts rather update on commit_form when changes made in records

Question

I have created a form in forms builder 10g. These are 3 tables.
1. Recovery_Shift (Production Shift Information) -- Parent Table
2. Recovery_Size (Many Size in one Production Shift) -- Child to Table- 1
3. Recovery_Size_Dtl (Details of the Size Recovered) -- Child to Table- 2
The form has been created using 3 datablocks correpsonding to the above tables in two canvases.
In second canvas I have a "Save" Push Button with code "Commit_Form". Whenever I am inserting first time it is ok. After pressing this push button if I make any changes in any record and press the Save button, forms shows unique constraint error. When I disable this constraint in table. The form inserts a new duplicate row in the table.
The problem is ==>if I make any changes in the form after pressing "Save" button (Commit_form) it inserts the whole row rather updating the row.
What could be the cause and solution. Please guide. The module is at implimentation stage. Thanks in advance for guidance.
Tables for your references.
Table - 1. Recovery_Shift
SHIFT_ID----------NUMBER(10,0)     --> PK
RECOVERY_DATE-----DATE     
SHIFT-------------VARCHAR2(1 Bytes)     
SHIFT_START_TIME--DATE     
SHIFT_END_TIME----DATE     
SUPERVISOR--------VARCHAR2(6 Bytes)     
OPT---------------VARCHAR2(6 Bytes)     
ENTRY_BY----------VARCHAR2(6 Bytes)     
ENTRY_DATE--------DATE     
VALIDATE_BY-------VARCHAR2(6 Bytes)     
VALIDATION_DATE---DATE     
SHIFT_MINUTE------NUMBER(10,0)     
Table - 1. Recovery_Size
SIZE_ID-----------NUMBER(10,0)     --> PK
SHIFT_ID----------NUMBER(10,0)     --> FK
REJ_STAGE---------VARCHAR2(2 Bytes)     
ITEM_SIZE---------NUMBER(7,2)     
ITEM_CLASS--------NUMBER(4,2)     
ITEM_GROUP--------VARCHAR2(2 Bytes)     
ITEM_QUALITY------VARCHAR2(3 Bytes)     
RECOVERED_MTR-----NUMBER(10,2)     
RECOVERED_TON-----NUMBER(10,3)     
AUCTION_MTR-------NUMBER(10,2)     
AUCTION_TON-------NUMBER(10,3)     
ITEM_SPEC---------NUMBER(2,0)     
Table - 1. Recovery_Size_Dtl
SIZE_ID-----------NUMBER(10,0)     --> FK
LEN_MIN-----------NUMBER(4,2)     
LEN_MAX-----------NUMBER(4,2)     
REC_AUC-----------VARCHAR2(1 Bytes)     
PCS---------------NUMBER(10,0)     
MTR---------------NUMBER(10,2)     
TON---------------NUMBER(10,3)     
SEGMENT-----------VARCHAR2(1 Bytes)
Message was edited by:
Vinay Pandey

Answer 1

for inserting a row it asks for commitThat is normal behavior. When you update or create a record in the Recovery_Size_Detail block, you must commit the record before working on another record.
I think it may be the cause of problem that there are already saved (commited)records in the form when i am entering more records in 2nd & 3rd table and commiting them.If you are creating new records after the commit, and these new records are duplicates in the database, then the unique constraint error is expected. If you want to ensure the user is not creating duplicate records before trying to commit, then see this:
http://sheikyerbouti.developpez.com/duplicates/duplicates.htm
You might try creating the form with just two blocks:
First block (master): Recovery_Shift
Second block (detail) Recovery_Size
Get that to work and test it by updating and creating records. After you are pleased that it works, save it and then add the 3rd block as a detail block for the the 2nd block. Then you have this:
Block1. Recovery_Shift (master)
Block2. Recovery_Size (detail for block 1 and master for block 3)
Block3. Recovery_Size_Detail (detail for block 2)