Need help(I am a begner in Oracle)

Question

I am looking for a technical help that, suppose i have an data entry form for Items entry.when users entring(new items) the item_code i want to check it is already there in the table, if it is there i want to display all the fields in the same block.
how it is possible? i am looking for logic, as well as codes and triggers.
Thanks alot

Answer 1

I am looking for a technical help that, suppose i have an data entry form for Items entry.when users entring(new items) the item_code i want to check it is already there in the table, if it is there i want to display all the fields in the same block.
how it is possible? i am looking for logic, as well as codes and triggers.
Thanks alot One way to do this is to use a timer. Check to see if the item entered is already in the database in the when-validate-item trigger:
DECLARE
emp_exists NUMBER := 0;
timer_id     Timer := Find_Timer('Cust_Code_Exists');
one_millisec NUMBER(1) := 1;
BEGIN
SELECT COUNT(*)
INTO emp_exists
FROM CUSTOMER
WHERE CUSTOMER_CODE = :CUSTOMER.CUSTOMER_CODE;
IF (emp_exists > 0) THEN
message ('Customer code already exists!');
IF ID_NULL(timer_id) then
timer_id := CREATE_TIMER('Cust_Code_Exists',one_millisec,NO_REPEAT);
ELSE
SET_TIMER('Cust_Code_Exists',1,NO_REPEAT);
END IF;
RAISE Form_Trigger_Failure;
END IF;
END;
Then in your form level when-timer-expired trigger:
DECLARE
     old_where               VARCHAR2(100);
     new_where               VARCHAR2(100);
     tm_name VARCHAR2(40);
BEGIN
tm_name := Get_Application_Property(TIMER_NAME);
IF tm_name = 'CUST_CODE_EXISTS' THEN     
     old_where := GET_BLOCK_PROPERTY(:SYSTEM.CURSOR_BLOCK, DEFAULT_WHERE);
     new_where := 'customer_code = '''||:CUSTOMER.CUSTOMER_CODE||'''';
SET_BLOCK_PROPERTY(:SYSTEM.CURSOR_BLOCK, DEFAULT_WHERE, new_where);
CLEAR_BLOCK(NO_VALIDATE);
EXECUTE_QUERY;
SET_BLOCK_PROPERTY(:SYSTEM.CURSOR_BLOCK, DEFAULT_WHERE, old_where);
END IF;
END;
Hope this helps