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.
CREATE TABLE Time(
Tipo VARCHAR(15) PRIMARY KEY,
DataInizio DATE,
DataFine DATE NOT NULL);
INSERT INTO Time VALUES('PreIscrizione', '2017-02-01', '2017-04-30');
INSERT INTO Time VALUES('Candidatura', '2017-05-01', '2017-07-30');
CREATE TABLE PreIscrizione(
Studente VARCHAR(16) REFERENCES Persona ON DELETE CASCADE ON UPDATE CASCADE PRIMARY KEY,
DataPreIscrizione DATE CHECK(DataPreIscrizione<(SELECT DataFine FROM Time WHERE Tipo = 'PreIscrizione')));
The table PreIscrizione allows to sign up a student, but it has to be done before a date indicated in the table Time. Obviously what i wrote above doesn't work, but it explains my idea. Which is the right way to solve this?
Trying to insert dates into my SQL Server table, I am using the format YYYYMMDD
I'm getting this error
Msg 241, Level 16, State 1, Line 201
Conversion failed when converting date and/or time from character string
This is the table I created:
CREATE TABLE SupplierOrders
(
supplierOrderID CHAR(5) NOT NULL,
orderDate DATE NOT NULL,
orderTotal NUMERIC(20,1) NOT NULL,
status VARCHAR(25) NOT NULL,
orderReceiveDate DATE,
orderPaymentDate DATE ,
paymentRefNo DATE ,
quotationID CHAR(6) NOT NULL UNIQUE,
PRIMARY KEY (supplierOrderID),
foreign key (quotationID)
references QuotationProduct(quotationID)
on update cascade on delete no action
);
and this is the data I'm trying to insert
INSERT INTO SupplierOrders
VALUES('s9021', '20150101', 10, 'delivered', '20150101', '20150101', 'po900', 'qo1021');
What am I doing wrong?
The problem is this column in your table.
paymentRefNo DATE ,
I think maybe you meant to make it a char or varchar.
You are trying to insert 'po900' into it.
Im inserting values into this table
CREATE TABLE Flight (
FlightNumber char(7) primary key,
ArrivalAirportCode char(6) references Airport (Airport_code),
DepartureAirportCode char(6) references Airport (Airport_code),
AircraftNumber varchar2(25) references Aircraft (AircraftNumber),
ArrivalDate date,
ArrivalTime Varchar2(5),
DepartureDate date,
DepartureTime varchar2(5)
);
and here are the values Im inserting into it
INSERT INTO FLIGHT values
('CA3048',
'LHR',
'EDI',
'N859E',
'14-NOV-2014',
'22:15',
'14-NOV-2014',
'20:15');
And I get the column not allowed here error for the 2nd date I insert, but not the first one. I've tried putting quotes around the date but I just get another error.
'14-NOV-2014'
Why are you inserting a string in a DATE column? '14-NOV-2014' is a STRING and NOT a DATE. You should not depend on implicit data type conversion.
Always, convert the string into a DATE explicitly using TO_DATE and proper format mask.
For example,
TO_DATE('14-NOV-2014','DD-MON-YYYY')
One more thing,
DepartureTime varchar2(5)
Makes no sense. You already have a DATE column, a DATE would have the time element too.
No need of a separate time column. A DATE has both date and time elements stored in 7 bytes.
Oracle stores DATE in total of 7 bytes. Each byte in it stores values for an element of the DATE as follows:
Byte Description
---- ------------------------------------------------
1 Century value but before storing it add 100 to it
2 Year and 100 is added to it before storing
3 Month
4 Day of the month
5 Hours but add 1 before storing it
6 Minutes but add 1 before storing it
7 Seconds but add 1 before storing it
All you need to do is just have 2 DATE columns:
CREATE TABLE Flight (
FlightNumber char(7) primary key,
ArrivalAirportCode char(6) references Airport (Airport_code),
DepartureAirportCode char(6) references Airport (Airport_code),
AircraftNumber varchar2(25) references Aircraft (AircraftNumber),
ArrivalDate date,
DepartureDate date
);
And then insert the values as:
INSERT INTO FLIGHT values
('CA3048',
'LHR',
'EDI',
'N859E',
TO_DATE('14-NOV-2014 22:15:00','DD-MON-YYYY HH24:MI:SS'),
TO_DATE('14-NOV-2014 20:15:00','DD-MON-YYYY HH24:MI:SS')
);
Update
As mentioned in the comments by #GriffeyDog and #a_horse_with_no_name.
Alternatively, you could also the ANSI literal instead, for example:
timestamp '2014-11-14 22:15'
I would like to learn a declarative approach for a data constraint issue I have had from time to time related to exclusive date ranges.
Below is a simplified example. I have items and prices on those items. I want the effective date range of the prices to be mutually exclusive with no overlap.
As I understand things with Oracle, user-defined functions are not eligible for use in CONSTRAINT declarations - and I can't even imagine how poorly it would perform if it were allowed. So I require a procedural approach using triggers. Typical trigger source is also included below.
I am not interested in learning better procedural logic for use within the trigger (it is just a simple demonstrative example). I am interested in learning a more declarative solution to a relatively popular data constraint issue I (and likely others) face.
I want to eliminate trigger-based solutions whenever I can, as a practice. However I can't seem to find my way out of this requirement without a trigger.
create table item ( title varchar2(32) primary key );
create table price (
item varchar2(32) not null references item (title),
price number(9,2),
effective_from date not null,
effective_to date not null,
constraint price_from_to_ck check (effective_to > effective_from ));
[REDACTED]
*(A combination of row and statement level triggers inteneded to prevent logical chronological overlap)
insert into item values ('LETTUCE');
insert into item values ('WHISKY');
insert into price values ( 'LETTUCE', 1.05, date '2013-01-01', date '2013-03-31' );
insert into price values ( 'LETTUCE', 1.08, date '2013-04-01', date '2013-06-30' );
insert into price values ( 'WHISKY', 33.99, date '2013-01-01', date '2013-05-31' );
insert into price values ( 'WHISKY', 31.15, date '2013-06-01', date '2013-07-31' );
-- should fail
insert into price values ( 'WHISKY', 30.55, date '2013-05-15', date '2013-06-05' );
While waiting for next Oracle 12c version, which supports Temporal Validity, I still use next approach:
create table item ( title varchar2(32) primary key );
create table price (
price_id number primary key,
item varchar2(32) not null references item (title),
price number(9,2),
effective_from date not null,
effective_to date not null,
effective_prev_to date,
constraint price_from_to_ck check ( effective_to > effective_from ),
constraint price_to_prev_ck check ( effective_from = effective_prev_to + 1 ),
constraint price_from_uq unique ( item, effective_to ),
constraint price_dates_chain_fk foreign key ( item, effective_prev_to ) references price ( item, effective_to ) );
insert into item values ('LETTUCE');
insert into item values ('WHISKY');
insert into price values ( 1, 'LETTUCE', 1.05, date '2013-01-01', date '2013-03-31', null );
insert into price values ( 2, 'LETTUCE', 1.08, date '2013-04-01', date '2013-06-30', date '2013-03-31' );
insert into price values ( 3, 'WHISKY', 33.99, date '2013-01-01', date '2013-05-31', null );
insert into price values ( 4, 'WHISKY', 31.15, date '2013-06-01', date '2013-07-31', date '2013-05-31' );
Let's try:
insert into price values ( 5, 'WHISKY', 30.55, date '2013-05-15', date '2013-06-05', date '2013-05-14' );
ORA-02291: integrity constraint (USER_4_E7DF1.PRICE_DATES_CHAIN_FK) violated - parent key not found : insert into price values ( 'WHISKY', 30.55, date '2013-05-15', date '2013-06-05', date '2013-05-14' )
But now updating and deleting dates in the middle of the chain is pain in the ass. It needs to change preceding and following rows in one statement with MERGE. That's why I've added price_id column, because you can't update a key in MERGE -- so, you need another key instead of (item, effective_%).
You can do this declaritively with a materialized view, as first suggested by Brian Camire. Here's an example:
--Original tables (with an extra primary key on PRICE)
create table item ( title varchar2(32) primary key );
create table price (
id number primary key,
item varchar2(32) not null references item (title),
price number(9,2),
effective_from date not null,
effective_to date not null,
constraint price_from_to_ck check (effective_to > effective_from ));
create materialized view log on price with rowid;
--Items with overlapping dates
create materialized view price_no_overlap_mv
refresh fast on commit as
select 'overlapping row' as dummy, price1.rowid rowid1, price2.rowid rowid2
from price price1, price price2
where
--Same item
price1.item = price2.item
--Overlapping dates
and (price1.effective_from <= price2.effective_to and price1.effective_to >= price2.effective_from)
--Don't compare the same row
and price1.id <> price2.id
;
--Throw an error if any rows ever get created.
alter table price_no_overlap_mv
add constraint price_no_overlap_mv_ck check (dummy = 'no rows allowed');
insert into item values ('LETTUCE');
insert into item values ('WHISKY');
insert into price values (1, 'LETTUCE', 1.05, date '2013-01-01', date '2013-03-31' );
insert into price values (2, 'LETTUCE', 1.08, date '2013-04-01', date '2013-06-30' );
insert into price values (3, 'WHISKY', 33.99, date '2013-01-01', date '2013-05-31' );
insert into price values (4, 'WHISKY', 31.15, date '2013-06-01', date '2013-07-31' );
commit;
-- should fail
insert into price values (5, 'WHISKY', 30.55, date '2013-05-15', date '2013-06-05' );
commit;
ORA-12008: error in materialized view refresh path
ORA-02290: check constraint (JHELLER.PRICE_NO_OVERLAP_MV_CK) violated
This declarative approach is both concurrent and consistent. But there are a lot of draw backs:
Materialized view logs, which are required for a fast refresh, are only supported in Enterprise Edition.
Your table needs a primary key, although you probably already have one but just didn't include it in the example.
Although declarative, the solution is still not straight-forward. You have to declare the opposite condition, and then check that it never exists.
Getting FAST REFRESH to work can be a nightmare for more than the simplest of queries. Even for this simple example, I had to use the old-style joins and had to add useless ROWIDs.
The constraint is not enforced until a COMMIT. Although that could be a positive thing, as many types of changes would temporarily create overlapping results. If you never allow overlapping results, you have to modify the table in a specific order.