| |
by: Agoston Bejo |
last post by:
I want to enforce such a constraint on a column that would ensure that the
values be all unique, but this wouldn't apply to NULL values. (I.e. there
may be more than one NULL value in the column.)
How can I achieve this?
I suppose I would get the most-hated "table/view is changing,
trigger/function may not see it" error if I tried to write a trigger that
checks the uniqueness of non-null values upon insert/update.
|
by: wireless |
last post by:
I've written code that dynamically builds an sql query based on
various constraint possibilities.
The problem is the code would have been very complex had I not come up
with a dummy constraint as a kind of place holder in the statement.
To avoid complex logic that determines if there was another constraint
before any other constraint and hence the need to add, say, AND or
not, I came up with a dummy constraint so that every subsequent...
|
by: adammitchell |
last post by:
How can you indicate that a FOREIGN KEY constraint references two
columns in two different tables?
"SQL Server Books Online" show an example of how to reference two
columns in the SAME table:
REFERENCES ref_table )
Here is the error and the 'bad' SQL code:
Server: Msg 8148, Level 16, State 1, Line 4
|
by: ferg |
last post by:
I have a Customer table. The table has two different CHECK constraints.
Then there is the Customer details dialog, which provides the user with
an UI for changing users. I have some UPDATE sql, which is called once
the user clicks the OK button on this dialog.
try
{
int rows = cmd.ExecuteNonQuery();
}
catch(SqlException se)
|
by: Jeff Kish |
last post by:
Hi.
I'm getting errors like this when I try to run an upgrade script I'm trying to
write/test:
altering labels to length 60
Server: Msg 5074, Level 16, State 4, Line 5
The object 'ALTPART_ANNOT_ANNOTID_FK' is dependent on column 'label'.
I used this to bracket my script:
|
| |
by: Laurence |
last post by:
Hi there,
How to differentiate between unique constraint and unique index? These
are very similar but I cannot differentiate them?
Could someone give me a hand?
Thanks in advance
|
by: antpal |
last post by:
I am not sure exactly what i am doing run but when I run this code in sql plus i get constraint error on most of my tables except author and books table. Please help I am new to Programming in PL/SQL.
--Create All Tables
CREATE TABLE authors (
auth_id NUMBER(7),
f_name VARCHAR2(30),
l_name VARCHAR2(50),
|
by: Kenneth Koenraadt |
last post by:
Hi Wing,
The utility Oracle offers for that is *check constraints*.
For instance :
ALTER TABLE Demerit ADD CONSTRAINT a1 CHECK (points between 1 and 6);
ALTER TABLE Demerit ADD CONSTRAINT a2 CHECK (dem_code <= 20 or
dem_code 20 and points <=3);
|
by: Frank Swarbrick |
last post by:
I have the following three tables
DROP TABLE CALLTRAK.SERVICE_CODES
@
CREATE TABLE CALLTRAK.SERVICE_CODES (
CODE CHAR(1) NOT NULL
, CONSTRAINT SERVICE_CODES_PK
PRIMARY KEY (CODE)
, DESCRIPTION VARCHAR(50) NOT NULL
)
|
by: rorajoey |
last post by:
Violation of UNIQUE KEY constraint 'IX_surveyQuestions'. Cannot insert duplicate key in object 'dbo.surveyQuestions'.
This might seem like a simple matter of trying to insert a row with ID=20 when there's already one with that ID, but the problem is a bit more complicated. The table is supposed to auto-increment the value for the primary key when a new record is inserted. But no matter what I do, I can't seem to insert more than one record...
|
by: Hystou |
last post by:
Most computers default to English, but sometimes we require a different language, especially when relocating. Forgot to request a specific language before your computer shipped? No problem! You can effortlessly switch the default language on Windows 10 without reinstalling. I'll walk you through it.
First, let's disable language synchronization. With a Microsoft account, language settings sync across devices. To prevent any complications,...
|
| |
by: Oralloy |
last post by:
Hello folks,
I am unable to find appropriate documentation on the type promotion of bit-fields when using the generalised comparison operator "<=>".
The problem is that using the GNU compilers, it seems that the internal comparison operator "<=>" tries to promote arguments from unsigned to signed.
This is as boiled down as I can make it.
Here is my compilation command:
g++-12 -std=c++20 -Wnarrowing bit_field.cpp
Here is the code in...
|
by: Hystou |
last post by:
Overview:
Windows 11 and 10 have less user interface control over operating system update behaviour than previous versions of Windows. In Windows 11 and 10, there is no way to turn off the Windows Update option using the Control Panel or Settings app; it automatically checks for updates and installs any it finds, whether you like it or not. For most users, this new feature is actually very convenient. If you want to control the update process,...
|
by: tracyyun |
last post by:
Dear forum friends,
With the development of smart home technology, a variety of wireless communication protocols have appeared on the market, such as Zigbee, Z-Wave, Wi-Fi, Bluetooth, etc. Each protocol has its own unique characteristics and advantages, but as a user who is planning to build a smart home system, I am a bit confused by the choice of these technologies. I'm particularly interested in Zigbee because I've heard it does some...
|
by: isladogs |
last post by:
The next Access Europe User Group meeting will be on Wednesday 1 May 2024 starting at 18:00 UK time (6PM UTC+1) and finishing by 19:30 (7.30PM).
In this session, we are pleased to welcome a new presenter, Adolph Dupré who will be discussing some powerful techniques for using class modules.
He will explain when you may want to use classes instead of User Defined Types (UDT). For example, to manage the data in unbound forms.
Adolph will...
|
by: conductexam |
last post by:
I have .net C# application in which I am extracting data from word file and save it in database particularly. To store word all data as it is I am converting the whole word file firstly in HTML and then checking html paragraph one by one.
At the time of converting from word file to html my equations which are in the word document file was convert into image.
Globals.ThisAddIn.Application.ActiveDocument.Select();...
|
by: adsilva |
last post by:
A Windows Forms form does not have the event Unload, like VB6. What one acts like?
|
| |
by: 6302768590 |
last post by:
Hai team
i want code for transfer the data from one system to another through IP address by using C# our system has to for every 5mins then we have to update the data what the data is updated we have to send another system
|
by: muto222 |
last post by:
How can i add a mobile payment intergratation into php mysql website.
|
1
