I am using Light switch on Azure.
After I modified a column in a record when I click the Save button I got
"Store update, insert, or delete statement affected an unexpected number of rows(0). Entties may have been modified or deleted since entities were loaded, Refresh ObjectStateManager entries.
I use VS 2012 on my dev machine debug this light switch app. it works fine and no errors when I modify the save column on same records then save it.
Is anybody in this forum has idea what could cause this? and how should I work around it?
I suspect the azure machine don't have the same version of EF with my dev machine. but in the Light switch project both client and server reference I could not find the EF is referenced there. So I don't know how I can bring the EF dll on my machine up to Azure machine.
Anybody could give me some suggestion on this?
Thanks
Chris
Usually it's a side effect of Optimistic Concurrency. This article can give you the idea of it in Lightswitch:
LightSwitch 2012 Concurrency Enhancements
When it's working on dev machine and it's not working on Azure, I guess something is not right in your production database.
you can also take a look at Entity framework: affected an unexpected number of rows(0)
Having Instead of insert/update triggers, sometimes SQL server does not report back an IdentityScope for each new inserted/updated row. Therefore EF can not realize the number of affected rows.
Normally, any insert/update into a table with identity column are immediately followed by a select of the scope_identity() to populate the associated value in the Entity Framework. The instead of trigger causes this second step to be missed, which leads to the 0 rows inserted error.
You can change your trigger to be either before or after insert or tweak your trigger by adding following line at the end of it:
select [Id] from [dbo].[TableXXX] where ##ROWCOUNT > 0 and [Id] = scope_identity()
Find more details in this or this thread.
Related
I am using Entity Framework and I have a table that I use to record some events that gets generated by a 3rd party. These events are valid for 3 days. So I like to clean out any events that is older than 3 days to keep my database table leaner. Is there anyway I can do this? Some approach that won't cause any performance issue during clean up.
To do the mentioned above there are some options :
1) Define stored procedure mapped to your EF . And you can use Quarts Trigger to execute this method using timely manner.
https://www.quartz-scheduler.net
2) SQL Server Agent job which runs every day at the least peak time and remove your rows.
https://learn.microsoft.com/en-us/sql/ssms/agent/schedule-a-job?view=sql-server-2017
If only the method required for cleaning purpose nothing else i recommend you go with option 2
first of all. Make sure the 3rd party write a timestamp on every record, in that way you will be able to track how old the record is.
then. Create a script that deletes all record that are older than 3 days.
DELETE FROM yourTable WHERE DATEDIFF(day,getdate(),thatColumn) < -3
now create a scheduled task in SQL management Studio:
In SQL Management Studio, navigate to the server, then expand the SQL Server Agent item, and finally the Jobs folder to view, edit, add scheduled jobs.
set script to run once every day or whatever please you :)
What does error 208 means? the query:
dependencies
| where type == "SQL" and success == "False"
| summarize count() by resultCode
is giving me 4500+ itens on the last hour alone and I can't seem to find any solid documentation about this.
Details:
The frequency of error rises as concurrency rises, meaning 1000 concurrent requests will generate more erros than 1000 sequential ones.
My application is Asp.Net MVC 4 framework 4.6 using latest EF
The error is intermittent. Performing a certain operation won't definitely result in the error
I don't think that this error means "Invalid Object Name" (as per other threads) because i can see EF auto-retrying this and eventually it goes through and the whole request is successfully returned (otherwise i would have A LOT of missed phone calls...)
The error occurs on both ASYNC and sync requests
I got in touch with MS support and according to them, this is caused by entity framework. Apparently EF keeps looking for 2 tables (migrationsHistory and edmMetadata) that I deliberately deleted. although that makes sense, i don't know why that error does not present itself on our in-house tests (the table are not present on the in-house dev env too...)
Above answer is correct however Id like to add additional information:
You need to have MigrationHistory table and it has to be populated correctly. edmMetadata is old table which was replaced by MigrationHistory so no need to worry about that.
Just by adding MigrationHistory tabled did not solve the issue completely ( I was down to 3 exceptions 208 from 5 ).
However, keep in mind that populating MigrationHistory table will render your dbContext out of sync if latest migration is not inserted in MigrationHistory!
Best way to get this is to issue:
UpdateDatabase -script
command and copy CREATE/INSERT/UPDATE statements from there.
Using Visual Studio Enterprise 2015
I would like to use schema compare to update a bunch of table changes from a test environment to my local one.
I'm getting the error:
Rows were detected. The schema update is terminating because data loss
might occur.
So this is saying I have data in the tables I want to update and I could lose data if I made the table changes. But I'm going to do a data compare afterward the get the updated data as well. How can I override the above error and force the changes? Or do I have to just truncate the tables with data in them first?
Thank you in advance
I found the answer in the settings.
Click on the options Cog wheel that's next to the compare and update buttons.
Next click on the General tab and then uncheck "Block on possible data loss"
Hope this helps someone in the future.
I have searched Google, BOL, and several forums and can't find the answer:
I have a very small data base application that I write some queries and SPs to extract data. A few days ago I opened an exsiting SP to find that something had added code similar to that below, sometimes multiple lines referring to every table in the database. When I set up a new simple SP like "Select * from TinyTable" and re-open it, the same code has been inserted.
The last thing I remember doing was reviewing the settings for results to grid in SSMS 2008 R2. I'm afraid I may have accidently changed a setting but I've spent hours reviewing them and can't identify what it might be.
I have considered reinstalling SSMS to set back to defaults but I have a linked server set up to solve a collation conflict, and don't want to cause problems with that. If anyone can point me in the right direction I'd appreciate it. I may be searching using the wrong terminology but can find nothing. As I say, I don't know for sure a change to the SSMS tools options is the problem but I suspect it could be something I have done.
Here's a sample of what gets automatically inserted at the bottom of every one of my procs:
GO
ALTER TABLE [dbo].[tblLot] WITH CHECK ADD CONSTRAINT [FK_tblLot_tblLocation] FOREIGN KEY([LocID])
REFERENCES [dbo].[tblLocation] ([LocID])
You likely have Tools > Options > SQL Server Object Explorer > Scripting > Object Scripting Options > Generate script for dependent objects set to True. Try changing the value to false.
I used SQL Server Management Studio to create 3 tables using SQL statements.
Then I attempted to create an ADO object in Visual Studio. The ADO wizard saw my database, but not the tables I created.
Is this because I need to somehow commit the changes I've made in Management Studio?
Or do I need to add some kind of prefix to the table names like:
CREATE TABLE mydb.Table1 ... ?
Or could this be a permissions thing?
Or am I not waiting enough time (1 min or so) for the ADO wizard to grab the table names from the database?
Ah, I guess when you script the creation of your tables (or anything else you're adding) you need to add this:
USE [Interview_MicahHoover]
GO
So much for relying on the ETL guy to set things up ;)
I figured this out by using the GUI to create the table, then right clicking on the new table in the left menu and saying 'CREATE TO ... clipboard', pasting into notepad, and looking at how the SQL Server Management Studio did it.