So, my issue is that I am trying to make something that will easily load in Excel datasheets into a SQL database, but before this I have to try and make the identity specification cooperate with me.
The issue begins when I assign the primary key with identity specification being true, as then I get the error message "Cannot insert explicit value for identity column in table 'Priskod' when IDENTITY_INSERT is set to OFF."
However when I set that identity specification is false, then I get the error message "Violation of PRIMARY KEY constraint 'PK_dbo.Priskod'. Cannot insert duplicate key in object 'dbo.Priskod'. The duplicate key value is (0). The statement has been terminated."
Does anyone have any suggestions about how I can fix this?
It sound like you have an Excel spreadsheet that holds data that you want to import into a SQL Server table.
The issue is that you are trying to load it directly in to the source table and to enable this, you are disabling the IDENTITY column. This should ring alarm bells really, as SQL is right when it prevents you from inserting duplicate keys.
There are 2 options here:
The key values in Excel are true identity values that are unique, so you will only INSERT records they don't exist in the target table. This would probably be best achieved by importing to a staging/temp table first and the inserting where the ID doesn't exist. You may also want to perform an UPDATE on rows where the ID does exist.
The key values in Excel are NOT true identity values.
Either way, I think you should add a new column to your target table like: ExternalId, which can be duplicated if required or checked against to prevent duplicates. With both approaches, you should leave the IDENTITY insert as it is.
Got the system to work now.
I had to enter the information straight into the database instead of actually trying to upload the information into the database itself. So thanks everyone for your help and support. You are all super.
Related
I am using NDbUnit to unit test my data access layer.
Everything has been working fine when constructing the XSD and associated XML files that are used to populate various tables with rows of data. However I have just noticed that I am unable to set the PK directly through XML for an integer PK column when it is an identity column.
i.e. When the database automatically handles incrementing and setting the PK on a row insertion, NDbUnit isn't able to override this and set it itself (as far as I can see).
Is there some way for NDbUnit to override this identity column value and set it directly from the XML or am I stuck with the auto-incremented value that SQL Server creates for the inserted row? Or is there another pattern that I should use to insert a row with an identity column and then subsequently use that value as the FK on another table's row?
Update:
I discovered that when you perform the NDbUnit database operation you need to set the parameter to InsertIdentity not just Insert:
INDbUnitTest database = new NDbUnit.Core.SqlClient.SqlDbUnitTest(connectionString);
database.PerformDbOperation(DbOperationFlag.InsertIdentity);
However even after I made this change, I now get the following error as the rows are being inserted:
Cannot insert explicit value for identity column in table 'myTable'
when IDENTITY_INSERT is set to OFF.
This would leave me to believe that the InsertIdentity flag being set on the NBDUnit method is not actually setting the IDENTITY_INSERT to OFF for the specific table within SQL Server.
Any suggestions on why this wouldn't be happening?
Better late than never hopefully but I experienced the same problem today.
On your XSD, highlight the identity column and hit F4. When the Properties pane comes up you'll probably see that AutoIncrement is set to False. Change this to True and it should start to work. Not sure why this happens on random occasions but hopefully this will help you out.
I have a requirement to change a "broken" computed column in a table to an identity column and as part of this work update some of the field values. This column is a pseudo primary key so doesn't have any constraints defined against it. I therefore need to determine if any other tables in the database contain a pseudo foreign key back to this column.
Before writing something myself I'd like to know if there is a script/tool in existence that when given a value (not a column name) can search across the data in all of the tables within an SQL Server database and show where that value exists?
Thanks in advance.
Quick google found this page/script:
http://vyaskn.tripod.com/search_all_columns_in_all_tables.htm
I don't personally know of a pretty GUI-interfaced utility that'll do it.
To prevent duplicate table entries in a database I use a primary key. I just add the information and if it is a duplicate then the primary will be a duplicate and it will not add to the table.
Should I also do a SQL query (before trying to add to the database) to see if the entry exists? Or is this redundant since I already have the primary key set?
It is redundant to check for presence of a value if you already have a constraint to prevent duplicates.
But it would also be ineffective to check before you insert, because some other concurrent client might insert that value in the moment between your check and your insert. So even if you check first, you'd still need to handle duplicate key errors.
Defining "unique constraint" on table with desired column will fix everything. If there's a dupplicate you will get error.
With most database platforms, when you create the primary key, the operation will fail if there are duplicate entries, so there should be no need to test for this beforehand.
Usually you'd get an exception or an error code from the call to SQL engine. If you need to handle that or not depends on your application logic. For example if it is a new username, and it already exists in the database, then exception is part of you application logic, and you will provide new user with a message about why registration failed.
I have a development database that has fees in it. It has a feeid, which is a unique key that is the identifier. The problem I run into is that the feeid/fee amount may not match when putting updating the table on a production server. This obviously could lead to some bad things happening, like overcharging for something or undercharging. Is there a way to match reset identities in sql server or match them or is this an example of when you would not want to use them?
Don't make your primary keys
"mean something" other than
identifying an unique record. If you
need to hard code an ID somewhere,
create another column for it.
So-called "natural keys" are more
trouble than they're worth
If,
for some reason, you decide that
either you will not or cannot follow
the first rule, don't use any
automatically generated key values.
That is the behaviour of an identity column, this is also what makes it so fast because it doesn't lock the table
to reset an identity either use DBCC CHECKIDENT or TRUNCATE TABLE
to insert IDs from one table to another and to keep the same values you need to do
SET IDENTITIY_INSERT ON
--upddate/insert rows
SET IDENTITIY_INSERT OFF
keep in mind that during the time between the two SET IDENTITIY_INSERT statements that your regular inserts will FAIL!
You can set IDENTITIY INSERT ON, update the IDs (make sure there are no conflicts) and then turn it back off.
I'm building an ASP.Net/MVC application using SQL 2008 Developer edition and a DB in Sql2005 compatibility mode. Using Entity Framework as DAL.
My problem is that I have a table where I'm using the integer identity column in a like an Invoice Number, that is, it always has to be unique and never reused. So using the GUID column type won't work without a substantial effort.
What I'm seeing is that the DB is filling in the gaps in the identity column. This will cause me long term problems. Is there a setting to disable this "filling in"
That sounds like something outside SQL server; SQL server does not "go back" and re-use gaps in identities unless the table's been reseeded, but even then it will blindly increment one-by-one and probably return a lot of duplicate key errors as it hits rows with existing values.
Are you sure the column is an identity? Is there anything else that might be re-assigning keys and/or turning on identity insert when creating rows?
SQL Server does not fill in the gaps of an identity field by default it will just keep going up in numbers as you insert rows.
It is possible to reset the identity back to 1 and therefore you may then see what you are describing.
Can I suggest you post some code / db structure that shows your problem and search for any code you may have that my perform an identity reseed.
Unless I am not understanding your issue correctly. If you create a primary key on your identity column, or a unique constraint, you can avoid the issue of duplicate values.
For example:
create table TableName
(
InvoiceID int identity(1,1) not null primary key
)