Is it possible to add data integrity between columns in different tables in SQL Server?
I have table Pay with column Date and table Orders with column DateofOrder. And I would like to add the data integrity so the Date cannot be earlier than the DateofOrder.
And when the user insert there the same date or even earlier database would show error.
I think you mean something like this, here done with a trigger;
CREATE TRIGGER trig_pay ON Pay
FOR INSERT, UPDATE
AS
IF EXISTS(SELECT *
FROM [Order] o
JOIN inserted i
ON o.id = i.payment_id
WHERE DateOfOrder>[date])
BEGIN
RAISERROR ('Sorry, Dave', 16, 1)
ROLLBACK;
RETURN;
END
INSERT INTO [Order] values (1, GETDATE()); -- Order today
INSERT INTO Pay values (1, DATEADD(dd, -1, getdate())); -- Pay yesterday
> Sorry, Dave
Yes, you can do it by using INSTEAD OF INSERT Trigger.
You would have to use an INSTEAD OF or AFTER trigger to enforce this, you can't do it declaratively. Well you could use a check constraint with a TVF or something but I've never tried that.
I'd show sample code but I'm not sure what payroll has to do with orders. If a new order comes in, what pay date must be later than or equal to the order date? Is there some other column that relates these two tables?
It is possible without resorting to triggers.
The idea is to add the DateofOrder in the Orders table to its existing key -- let's call it order_id -- to create a compound superkey, then reference this superkey (rather than the simple key solely order_id) in the Pay table.
Here are the bare bones:
CREATE TABLE Orders
(
order_id CHAR(10) NOT NULL,
DateofOrder DATE NOT NULL,
UNIQUE (order_id), -- simple candidate key
UNIQUE (DateofOrder, order_id) -- compund superkey
);
CREATE TABLE Pay
(
order_id CHAR(10) NOT NULL,
DateofOrder DATE NOT NULL,
FOREIGN KEY (DateofOrder, order_id)
REFERENCES Orders (DateofOrder, order_id),
DateOfPayment DATE NOT NULL,
CHECK (DateofOrder < DateOfPayment),
UNIQUE (order_id)
);
Related
I have been receiving the error code 1452, i am trying to add keys to a table to keep data unqiue and useable in other tables. i have created the tables and can use the information already entered but i want to make the databases properly so i am trying to use the keys. please refer to the code below.
CREATE TABLE CUSTOMERS (
CustID varchar(50) NOT NULL,
Client_Name varchar(50) NOT NULL,
Client_Address varchar(80) NOT NULL,
PRIMARY KEY (CustID)
);
CREATE TABLE ORDERS (
Order_ID VARCHAR(10) NOT NULL,
Client_NameID varchar(50) NOT NULL,
Dates varchar(10) NOT NULL,
PRIMARY KEY (Order_ID),
FOREIGN KEY (Client_NameID) REFERENCES CUSTOMERS(CustID)
);
SELECT * FROM CUSTOMERS;
SELECT * FROM ORDERS;
DESCRIBE Orders; /*Used to display the Table*/
ALTER TABLE ORDERS ADD Dates VARCHAR(10); /*Used to add columns into the table*/
ALTER TABLE ORDERS DROP COLUMN Date; /*Used to remove column from the table*/
INSERT INTO CUSTOMERS (CustID, Client_Name, Client_Address) VALUES
('168', 'Coventry Building Services', 'Units 2-4, Binley Industrial Estate, CV3 2WL'), /*Used to insert values into the columns*/
('527', 'Allied Construction LTD', '34, Lythalls La Industrial Estate, NG18 5AH'),
('169', 'Ricoh Builds Ltd', 'Unit 12, Stoneleigh Park, CV8 2UV'),
('32', 'British Embassy in Tehran', '198 Ferdowski Avenue Tehran 11316-91144 Iran');
INSERT INTO ORDERS (Order_ID, Client_NameID, Dates) VALUES
('CON-2237', 'Coventry Building Services', '2014-12-14'),
('CON-3664', 'Allied Construction LTD', '2015-01-16'),
('CON-2356', 'Ricoh Builds Ltd', '2015-02-12'),
('CON-1234', 'British Embassy in Tehran', '2015-04-16');
DELETE FROM ORDERS WHERE Client_Name='Coventry Building Services'; /*Used to delete specific
data from the specific row and column wherever applicable*/
DROP TABLE CUSTOMERS;
DROP TABLE ORDERS;
Below are the tables im trying to work with, all of them will pretty much have a key that links them together if necessary
The CustomerS Table which only includes a Primary Key
The Orders Table which includes a Primary and Foreign key
The problem is with the inserts into table orders. Your foreign key on Client_NameIDreferencesCUSTOMERS(CustID), but you are giving the CUSTOMERS(Client_Name) instead.
You probably want:
INSERT INTO ORDERS (Order_ID, Client_NameID, Dates) VALUES
('CON-2237', 'CON-2237', '2014-12-14');
('CON-3664', 'CON-3664', '2015-01-16');
('CON-2356', 'CON-2356', '2015-02-12');
('CON-1234', 'CON-1234', '2015-04-16');
Notes:
You can perform all inserts in a single query by passing several tuples of values, as shown above
Don't store dates as strings; instead, use the date datatype, which exists for that purpose. I changed the query so it uses proper date literals, which would fit in a date column
it is unclear why you want to use the same value for the primary key of customers and orders - to me, this makes things harder to follow. I would recommend just using auto-incremented primary keys
I'm trying to validate the columns in the table ProjectDetails.TimeCards
create table ProjectDetails.TimeCards(
Time_Card_ID int identity (55,15),
Employee_ID int foreign key references HumanResources.Employees(Employee_ID),
Date_Issued date, --DateIssued should be greater than the current date and the project start date (Project start date is from another table).
Days_Worked int constraint chk_Days_Worked check(Days_Worked > '0'),
Project_ID int foreign key references ProjectDetails.Projects(Project_ID),
Billable_hours int constraint chk_Billable_Hours check (Billable_Hours > '0'),
Total_Cost money, -- should be automatically calculated by using the following formula: TotalCost=Billable Hours * BillingRate (billing rate is from another table)
Work_Code_ID int foreign key references ProjectDetails.WorkCodes(Work_Code_ID)
);
I tried building a trigger, but was only able to get the trigger to fire if the Date_Issued was less than the current date
CREATE TRIGGER dateissued
ON ProjectDetails.TimeCards
FOR INSERT
AS
DECLARE #ModifiedDate date
SELECT #ModifiedDate = Date_Issued FROM Inserted
IF (#ModifiedDate < getdate())
BEGIN
PRINT 'The modified date should be the current date. Hence, cannot insert.'
ROLLBACK TRANSACTION -- transaction is to be rolled back
END
i need the trigger to fire if the Date issued is less than the current date and also if date issued is less than the start_date. As for the billing rate calculation i'm lost there.
This is the other table
create table ProjectDetails.Projects(
Project_ID int identity (0100, 01) primary key, -- Primary key
Project_Name char (50) not null,
Start_Date date not null, -- the start date i'm referring to
End_Date date not null,
constraint CheckEndLaterThanStart check (End_Date > Start_Date),
Billing_Estimate money constraint chk_Billing_Estimate check (Billing_Estimate > '1000'),
Client_ID int Foreign Key references CustomerDetails.Clients(Client_ID)
);
I believe this provides the logic you are after. There are a couple of comments in the code for you:
CREATE TRIGGER trg_chk_Date_Issued ON ProjectDetails.TimeCards
FOR INSERT, UPDATE --I assume on need on UPDATE as well, as otherwise this won't validate
AS BEGIN
IF EXISTS(SELECT 1
FROM inserted i
JOIN ProjectDetails.Projects P ON i.Project_ID = P.Project_ID
WHERE i.Date_Issued < CONVERT(date,GETDATE())
OR i.Date_Issued < P.Start_Date) BEGIN
RAISERROR(N'Date Issued cannot be less than the current date or the Project Start Date.', 10,1); --Raised an error, rather than using PRINT
ROLLBACK;
END
END
Note that you may want a different trigger for UPDATE, as if you are updating the row, and Date_Issued has a value lower than the date of the UPDATE, the statement will fail.
I have here a table that corresponds to the orders of the customers. I use AUTO_INCREMENT to determine the ID of the order. I have this SQL code to the orders table:
CREATE TABLE IF NOT EXISTS `orders` (
`order_id` int(11) NOT NULL AUTO_INCREMENT,
`customer_id` int(11) NOT NULL,
`customer_name` varchar(500) NOT NULL,
`order_total_price` decimal(20, 2) NOT NULL,
`order_date` varchar(100) NOT NULL,
PRIMARY KEY (`order_id`)
) ENGINE=InnoDB
What I need is to insert each of the products of that order in another table with a Foreign Key order_id to specify what order that products belongs to. The SQL code for the purchased_products table is:
CREATE TABLE IF NOT EXISTS `purchased_products` (
`order_id` int (11) NOT NULL,
FOREIGN KEY (`order_id`) REFERENCES orders(`order_id`),
`product_name` varchar(500) NOT NULL,
`product_price` decimal(20, 2) NOT NULL,
`product_quantity` int(11) NOT NULL,
PRIMARY KEY (`order_id`)
)
When the user buy something, I use this to insert the data in the orders table:
INSERT INTO orders (customer_id, customer_name, order_total_price, order_date)
VALUES ('{$customer_id}', '{$customer['customer_name']}', '{$order_total_price}', '{$order_date}')";
And here is my problem. I need to insert in the purchased_products table the products with the Order ID generated:
INSERT INTO purchased_products (order_id, product_name, product_price, product_quantity)
VALUES ('*/The ID of the order need to goes here*/', '{$product['product_name']}', '{$product['product_price']}', '{$product['quantity']}')";
This is giving me a headache. I'm not really knowing how to do it. This should be done by a different way? How do I associate the order ID to the products belonging to it?
use function last_insert_id(). it will give you value that was auto-incremented as last one before call to it.
You can get the get the last inserted primary key value by using ##IDENTITY
Here's the MSDN article: https://msdn.microsoft.com/en-us/library/ms187342.aspx
USE AdventureWorks2012;
GO
--Display the value of LocationID in the last row in the table.
SELECT MAX(LocationID) FROM Production.Location;
GO
INSERT INTO Production.Location (Name, CostRate, Availability, ModifiedDate)
VALUES ('Damaged Goods', 5, 2.5, GETDATE());
GO
SELECT ##IDENTITY AS 'Identity';
GO
--Display the value of LocationID of the newly inserted row.
SELECT MAX(LocationID) FROM Production.Location;
GO
I would also recommend wrapping the statement in a TRANSACTION so that if any errors occur you can rollback.
As others have commented it depends on the RDBMS. In Oracle you typically use sequences. You create and store the sequence on the database and can use it on an INSERT by doing sequencename.nextval().
Sequences let you control starting values, increment/decrement size, caching and a lot more.
I did it by using PDO lastInsertId() to get the ID of last inserted order:
$sql = "INSERT INTO orders (customer_id, customer_name, order_total_price, order_date)
VALUES ('{$customer_id}', '{$customer['customer_name']}', '{$order_total_price}', '{$order_date}')";
$query = $connection->prepare($sql);
$query->execute();
$respective_order_id = $connection->lastInsertId();
And then:
INSERT INTO purchased_products (order_id, product_name, product_price, product_quantity)
VALUES ('{$respective_order_id}', '{$product['product_name']}', '{$product['product_price']}', '{$product['quantity']}')";
Thanks for all who tried to help! They put me in the right way!
you can use SCOPE_IDENTITY() to retrieve the last identity you inserted within the current sql session.
here is another question with a great description of all the differences:
identity scope Question
I am trying to make a procedure that takes makes potential empty "received" fields use the current date. I made a sequence called Order_number_seq that populates the order number (Ono) column. I don't know how to link errors in the orders table to a entry in the Orders_errors table.
this is what i have so far:
CREATE PROCEDURE Add_Order
AS BEGIN
UPDATE Orders
CREATE Sequence Order_number_seq
Start with 1,
Increment by 1;
UPDATE Orders SET received = GETDATE WHERE received = null;
These are the tables I am working with:
Orders table
(
Ono Number Not Null,
Cno Number Not Null,
Eno Number Not Null,
Received Date Null,
Shipped_Date Date Null,
Creation_Date Date Not Null,
Created_By VARCHAR2(10) Not Null,
Last_Update_Date Date Not Null,
Last_Updated_By VARCHAR2(10) Not Null,
CONSTRAINT Ono_PK PRIMARY KEY (Ono),
CONSTRAINT Cno_FK FOREIGN KEY (Cno)
REFERENCES Customers_Proj2 (Cno)
);
and
Order_Errors table
(
Ono Number Not Null,
Transaction_Date Date Not Null,
Message VARCHAR(100) Not Null
);
Any help is appreciated, especially on linking the orders table errors to create a new entry in OrderErrors table.
Thanks in advance.
Contrary to Martin Drautzburg's answer, there is no foreign key for the order number on the Order_Errors table. There is an Ono column which appears to serve that purpose, but it is not a foreign as far as Oracle is concerned. To make it a foreign key, you need to add a constraint much like the Cno_FK on Orders. An example:
CREATE TABLE Order_Errors
(
Ono Number Not Null,
Transaction_Date Date Not Null,
Message VARCHAR(100) Not Null,
CONSTRAINT Order_Errors_Orders_FK FOREIGN KEY (Ono) REFERENCES Orders (Ono)
);
Or, if your Order_Errors table already exists and you don't want to drop it, you can use an ALTER TABLE statement:
ALTER TABLE Order_Errors
ADD CONSTRAINT Order_Errors_Orders_FK FOREIGN KEY (Ono) REFERENCES Orders (Ono)
;
As for the procedure, I'm inclined to say what you're trying to do does not lend itself well to a PROCEDURE. If your intention is that you want the row to use default values when inserted, a trigger is better suited for this purpose. (There is some performance hit to using a trigger, so that's a consideration.)
-- Create sequence to be used
CREATE SEQUENCE Order_Number_Sequence
START WITH 1
INCREMENT BY 1
/
-- Create trigger for insert
CREATE TRIGGER Orders_Insert_Trigger
BEFORE INSERT ON Orders
FOR EACH ROW
DECLARE
BEGIN
IF :NEW.Ono IS NULL
THEN
SELECT Order_Number_Sequence.NEXTVAL INTO :NEW.Ono FROM DUAL;
END IF;
IF :NEW.Received IS NULL
THEN
SELECT CURRENT_DATE INTO :NEW.O_Received FROM DUAL;
END IF;
END;
/
This trigger will then be executed on every single row inserted into the Orders table. It checks if the Ono column was NULL and replaces it with an ID from the sequence if so. (Be careful that you don't ever provide an ID that will later be generated by the sequence; it will get a primary key conflict error.) It then checks if the received date is NULL and sets it to the current date, using the CURRENT_DATE function (which I believe was one of the things you were trying to figure out), if so.
(Side note: Other databases may not require a trigger to do this and instead could use a default value. I believe PostgreSQL, for instance, allows the use of function calls in its DEFAULT clauses, and that is how its SERIAL auto-increment type is implemented.)
If you are merely trying to update existing data, I would think the UPDATE statements by themselves would suffice. Is there a reason this needs to be a PROCEDURE?
One other note. Order_Errors has no primary key. You probably want to have an auto-incrementating surrogate key column, or at least create an index on its Ono column if you only ever intend to select off that column.
There are a number of confusing things in your question:
(1) You are creating a sequence inside a procedure. Does this even compile?
(2) Your procedure does not have any parameters. It just updates the RECEIVED column of all rows.
(3) You are not telling us what you want in the MESSAGE column.
My impression is that you should first go "back to the books" before you ask questions here.
As for your original question
how to link errors in the orders table to a entry in the Orders_errors
table.
This is aleady (correctly) done. The Orders_error table contains an ONO foreign key which points to an order.
I have only done databases without relations, but now I need to do something more serious and correct.
Here is my database design:
Kunde = Customer
Vare = Product
Ordre = Order (Read: I want to make an order)
VareGruppe = ehm..type? (Read: Car, chair, closet etc.)
VareOrdre = Product_Orders
Here is my SQL (SQLite) schema:
CREATE TABLE Post (
Postnr INTEGER NOT NULL PRIMARY KEY,
Bynavn VARCHAR(50) NOT NULL
);
CREATE TABLE Kunde (
CPR INTEGER NOT NULL PRIMARY KEY,
Navn VARCHAR(50) NOT NULL,
Tlf INTEGER NOT NULL,
Adresse VARCHAR(50) NOT NULL,
Postnr INTEGER NOT NULL
CONSTRAINT fk_postnr_post REFERENCES Post(Postnr)
);
CREATE TABLE Varegruppe (
VGnr INTEGER PRIMARY KEY,
Typenavn VARCHAR(50) NOT NULL
);
CREATE TABLE Vare (
Vnr INTEGER PRIMARY KEY,
Navn VARCHAR(50) NOT NULL,
Pris DEC NOT NULL,
Beholdning INTEGER NOT NULL,
VGnr INTEGER NOT NULL
CONSTRAINT fk_varegruppevgnr_vgnr REFERENCES Varegruppe(VGnr)
);
CREATE TABLE Ordre (
Onr INTEGER PRIMARY KEY,
CPR INTEGER NOT NULL
CONSTRAINT fk_kundecpr_cpr REFERENCES Kunde(CPR),
Dato DATETIME NOT NULL,
SamletPris DEC NOT NULL
);
CREATE TABLE VareOrdre (
VareOrdreID INTEGER PRIMARY KEY,
Onr INTEGER NOT NULL
CONSTRAINT fk_ordrenr_onr REFERENCES Ordre(Onr),
Vnr INTEGER NOT NULL
CONSTRAINT fk_varevnr_vnr REFERENCES Vare(Vnr),
Antal INTEGER NOT NULL
);
It should work correctly.
But I am confused about Product_Orders.
How do I create an order? For example, 2 products using SQL INSERT INTO?
I can get nothing to work.
So far:
Only when I manually insert products and data into Product_Orders and then add that data to Orders = which makes it complete. Or the other way around (create an order in with 1 SQL, then manually inserting products into Product_orders - 1 SQL for each entry)
You should first create an order and then insert products in the table Product_Orders. This is necessary because you need an actual order with an id to associate it with the table Product_Orders.
You always should create a record in the foreign-key table before being able to create one in your current table. That way you should create a "Post", customer, type, product, order and product_order.
Try this ...
first you have to insert a customer
insert into kunde values(1, 'navn', 1, 'adresse', 1)
then you insert a type
insert into VareGruppe values(1, 'Type1')
then you insert a product
insert into vare values(1, 'product1', '10.0', 1, 1)
then you add an order
insert into ordre values(1, 1, '20090101', '10.0')
then you insert a register to the product_orders table
insert into VareOrdre values (1, 1, 1, 1)
I think this is it. :-)
As the primary keys are autoincrement, don't add them to the insert and specify the columns like this
insert into vare(Nav, Pris, Beholdning, VGnr) values('product1', '10.0', 1, 1)
Use Select ##identity to see the onr value
I think you already have the hang of what needs to happen. But what I think you are getting at is how to ensure data integrity.
This is where Transactions become important.
http://www.sqlteam.com/article/introduction-to-transactions
Is it the SalesPrice (I'm guessing that's what SamletPris means) that's causing the issue? I can see that being a problem here. One common design solution is to have 2 tables: Order and OrderLine. The Order is a header table - it will have the foreign key relationship to the Customer table, and any other 'top level' data. The OrderLine table has FK relationships to the Order table and to the Product table, along with quantity, unit price, etc. that are unique to an order's line item. Now, to get the sales price for an order, you sum the (unit price * quantity) of the OrderLine table for that order. Storing the SalesPrice for a whole order is likely to cause big issues down the line.
A note just in case this is MySQL: If you're using MyISAM, the MySQL server ignores the foreign keys completely. You have to set the engine to InnoDB if you want any kind of integrity actually enforced on the database end instead of just in your logic. This isn't your question but it is something to be aware of.
fbinder got the question right :)