I have a large detail table for which one column is a foreign key to a list of values/lookup table.
The BIRT report is on the detail table.
I want to select rows from the detail table given a user-selected value from the foreign key table.
Detail:
select id, o.owner_name, ....
from detail as d
inner join
owner as o
on (d.owner_id = o.owner_id)
where d.owner_id = ?
Foreign Key/LOV/Lookup table
select owner_id, owner_name
from owner;
So, on report execution, the user is presented with a pulldown menu populated with the owner_id/owner_name values from the owner table. The user selects the required owner_name whose owner_id value is then provided to the detail where clause parameter.
Is this possible?
I didn't see it after quite a bit of time looking, but in the end RTFM got me there.
Create two data sets, one for the detail the other for the lookup;
In report's parameters, see "Selection list values"/Dynamic
Related
I am implementing a Interactive grid to perform DML operations on a table.
it has combined primary key of two columns
One primary key column is display only and refer to master table and another primary key column I want to have a LOV to select value. LOV is dynamic lov having a display and return value picked from another table.
Inserts are fine but session state item value is set for one row and all the operations are performed on that same row irrespective of which row is selected.
you can see a sample here
https://apex.oracle.com/pls/apex/f?p=128616:2:1964277347439::NO:::
master table name: sample
detail table name: sample_child
primary key in sample child : ID and Name
pop lov is implemented in NAME
LOV values are picked from table: Sample_uncle
LOV display : ID || '-' || NAME
LOV return : ID
you can try to update blabla column of sample_child table to see the issue.
I am not sure how I can give you access to look at the implementation.
I have already tried all the options I can think of
This is to do with your primary keys, the detail table does not appear to have proper ones, thats why it always tried to update the first entry, and I think this is also why every row is marked when you load the table.
Primary keys also do the annoying thing of refusing to be empty, as you can see if you insert a new row, the middle column(which is a PK) is filled with 't1001'.
Since you are dealing with simple tables(and not a whole bunch of joined tables) I always consider it best to use ROWID as PK. So set ROWID as PK for the master table, and ROWID for the detail table. And have the detail table have a Master table be your master table, and then click on the first column in the detail table and set the master column for it. And I also personaly always hide the column that is linked.
I would advise you use ROWID whenever possible as its just so much easier to work with, it does mean you might need to set up a validation to prevent someone adding duplicated values for your actual PK, but since the PK is in the underlying table, they cant enter it anyways(but if you have a validation, the error will be much prettier), whilst if the column is a PK, APEX will prevent duplicates by default.
I hope this helps
I am working on this assignment question and it is asking me:
To create a table called (TEMP_CUST) from an existing table Customers
View the content and constraints of TEMP_CUST table
What I have done so far is I have created my table, didn't add any constraints to the table TEMP_CUST and viewed the table using the DESC command.
Here is the code for table creation
CREATE TABLE TEMP_CUST
AS
(SELECT
CUSTOMER#, LASTNAME,
FIRSTNAME, ADDRESS, CITY,
STATE, ZIP, REFERRED,
REGION, EMAIL
FROM
CUSTOMERS);
DESC TEMP_CUST;
Now that I have done that I want to view the constraints of the table. I have used this command but am not sure if it is correct.
SELECT *
FROM USER_CONSTRAINTS
WHERE TABLE_NAME = 'TEMP_CUST';
i have used this command, but not sure if it is correct.
You haven't said why you don't think it's correct so we have to guess the reason for your doubt. Perhaps it's because the set of constraints you get is smaller than the set of constraints for the original CUSTOMERS table?
That is correct. When we use CREATE TABLE ... AS SELECT the statement creates a new table with the projection, column names and datatypes of the original tables (assuming a vanilla SELECT clause) and the data (determined by the WHERE clause, if any). However, the only constraints which are created are NOT NULL constraints on the primary key column(s) and any other mandatory columns. The new table does not have primary key, foreign key or check constraints. We have to create these explicitly.
Hence, this query ...
SELECT * FROM USER_CONSTRAINTS
WHERE TABLE_NAME = 'TEMP_CUST';
... might return fewer constraints than you were expecting.
I'm using MS Access 2016.
Suppose I have a Student table, a Subject table (ie Geography, History etc) and a StudentSubject table that records which subjects each student has chosen.
StudentSubject contains StudentId and SubjectId as foreign keys.
No student is to choose more that 5 subjects.
Is there any way to define a validation rule on the table such that a given StudentId may not appear in the StudentSubject table more than 5 times?
I could enforce the contraint by introducing an additional table, but if possible, I like to avoid that.
I also want to define a constraint at table level, rather than use vba code that gets invoked when a record is inserted via a form. Access, as far as I know, has no such thing as triggers, as one would have in an sql system.
You can use a CHECK constraint to limit the possibilities:
ALTER TABLE StudentSubject
ADD CONSTRAINT Max5Subjects
CHECK(
NOT EXISTS(
SELECT 1
FROM StudentSubject
GROUP BY StudentID
HAVING Count(StudentID) > 5
)
)
Note that this might slow down data entry a bit, especially if StudentID is not indexed.
Check constraints need to be executed either in ANSI 92 compatible mode, or using ADO (e.g. using CurrentProject.Connection.Execute). More details here
To execute it using ADO, you can just use this single line in the immediate window:
CurrentProject.Connection.Execute "ALTER TABLE StudentSubject ADD CONSTRAINT Max5Subjects CHECK(NOT EXISTS( SELECT 1 FROM StudentSubject GROUP BY StudentID HAVING Count(StudentID) > 5))"
Also, keep in mind that if somehow there are records that violate the constraint (e.g. because they were present before the constraint got added), your table will get locked down fully.
I have a DM Form type page, where I would like to show and update values from different tables. By default when I created page, I have been asked for data source, specified only one of the tables, which in fact created process in After Header of type Automated Row Fetch. Also in After Submit a process of type Automatic Row Processing (DML) is created. When I add an item in the page from different table, obviously I am getting an error that the column not found in that table. How can I add more tables into that page, so they will be fetched and updated properly?
There is a common column in all tables, to identify which record I would like to show from each table.
I would like to show and update values from different tables
[...]
There is a common column in all tables, to identify which record I would like to show from each table.
Maybe are you looking for a simple JOIN on your various tables?
Based on Oracle's HR example schema, if you need to display both departments and employees names, you write something like that as your report query:
SELECT department_name as dep_name,
first_name || ' ' || last_name as emp_name
FROM HR.DEPARTMENTS JOIN HR.EMPLOYEES
USING(DEPARTMENT_ID)
In order for this to be usable from APEX form builder, you have to wrap it in a VIEW:
CREATE VIEWS MY_VIEW AS SELECT .... FROM ... JOIN ...
I can't guarantee that the view will be update-able out-of-the-box as Oracle has very specific rules for inherently updatable views -- especially for join views. However, you might be able to make your view updatable anyway by using an INSTEAD OF trigger. If you decide to go that way, maybe worth considering asking an other question on that specific topic if needed.
I have this table in an Oracle DB which has a primary key defined on 3 of the data columns. I want to drop the primary key constraint to allow rows with duplicate data for those columns, and create a new column, 'id', to contain an auto-incrementing integer ID for these rows. I know how to create a sequence and trigger to add an auto-incrementing ID for new rows added to the table, but is it possible to write a PL/SQL statement to add unique IDs to all the rows that are already in the table?
Once you have created the sequence:
update mytable
set id = mysequence.nextval;
If you're just using an integer for a sequence you could update the id with the rownum. e.g.
update
table
set id = rownum
You then need to reset the sequence to the next valid id.
Is this what you need?
UPDATE your_table
SET id = your_seq.nextval;
This assumes you don't care what order your primary keys are in.
First you should check your PCTFREE... is there enough room for every row to get longer?
If you chose a very small PCTFREE or your data has lots of lenght-increasing updates, you might begin chaining every row to do this as an update.
You almost certainly better to do this as a CTAS.
Create table t2 as select seq.nextval, t1.* from t1.
drop t1
rename t2 to t1.