firebird-net-provider

[Firebird-net-provider] Multithread insert

[Геннадий З. <zab...@gm...>]

I'm trying to insert to database multiple items at once via following code:

using (var transaction =
act.Database.BeginTransaction(System.Data.IsolationLevel.RepeatableRead))
{
  // inserting and updating several related entities.
  act.SaveChanges() // Throws exception
}

Exception message:
lock conflict on no wait transaction
deadlock
update conflicts with concurrent update
concurrent transaction number is 665378

A problematic query that throws is about updating the entity, that all
my queries update.

Using any other IsolationLevel doesn't affect the behavior.

Re: [Firebird-net-provider] Multithread insert

[Геннадий З. <zab...@gm...>]

I was wrong about IsolationLevel. If use Isolationlevel.Serializable
exception message changes to:

On 17 September 2015 at 17:32, Геннадий Забула <zab...@gm...> wrote:
> I'm trying to insert to database multiple items at once via following code:
>
> using (var transaction =
> act.Database.BeginTransaction(System.Data.IsolationLevel.RepeatableRead))
> {
>   // inserting and updating several related entities.
>   act.SaveChanges() // Throws exception
> }
>
> Exception message:
> lock conflict on no wait transaction
> deadlock
> update conflicts with concurrent update
> concurrent transaction number is 665378
>
> A problematic query that throws is about updating the entity, that all
> my queries update.
>
> Using any other IsolationLevel doesn't affect the behavior.

Re: [Firebird-net-provider] Multithread insert

[Геннадий З. <zab...@gm...>]

lock conflict on no wait transaction
Acquire lock for relation (<Table with simultenous updates>) failed
---> FirebirdSql.Data.Common.IscException: lock conflict on no wait
transaction
Acquire lock for relation (<Table with simultenous updates>) failed

On 17 September 2015 at 17:38, Геннадий Забула <zab...@gm...> wrote:
> I was wrong about IsolationLevel. If use Isolationlevel.Serializable
> exception message changes to:
>
> On 17 September 2015 at 17:32, Геннадий Забула <zab...@gm...> wrote:
>> I'm trying to insert to database multiple items at once via following code:
>>
>> using (var transaction =
>> act.Database.BeginTransaction(System.Data.IsolationLevel.RepeatableRead))
>> {
>>   // inserting and updating several related entities.
>>   act.SaveChanges() // Throws exception
>> }
>>
>> Exception message:
>> lock conflict on no wait transaction
>> deadlock
>> update conflicts with concurrent update
>> concurrent transaction number is 665378
>>
>> A problematic query that throws is about updating the entity, that all
>> my queries update.
>>
>> Using any other IsolationLevel doesn't affect the behavior.

Re: [Firebird-net-provider] Multithread insert

[Геннадий З. <zab...@gm...>]

Narrowed the problem. The cause is a multithreaded update of the same
record field. Transactions, as I said don't dispatch the issue.

On 17 September 2015 at 17:38, Геннадий Забула <zab...@gm...> wrote:
> lock conflict on no wait transaction
> Acquire lock for relation (<Table with simultenous updates>) failed
> ---> FirebirdSql.Data.Common.IscException: lock conflict on no wait
> transaction
> Acquire lock for relation (<Table with simultenous updates>) failed
>
> On 17 September 2015 at 17:38, Геннадий Забула <zab...@gm...> wrote:
>> I was wrong about IsolationLevel. If use Isolationlevel.Serializable
>> exception message changes to:
>>
>> On 17 September 2015 at 17:32, Геннадий Забула <zab...@gm...> wrote:
>>> I'm trying to insert to database multiple items at once via following code:
>>>
>>> using (var transaction =
>>> act.Database.BeginTransaction(System.Data.IsolationLevel.RepeatableRead))
>>> {
>>>   // inserting and updating several related entities.
>>>   act.SaveChanges() // Throws exception
>>> }
>>>
>>> Exception message:
>>> lock conflict on no wait transaction
>>> deadlock
>>> update conflicts with concurrent update
>>> concurrent transaction number is 665378
>>>
>>> A problematic query that throws is about updating the entity, that all
>>> my queries update.
>>>
>>> Using any other IsolationLevel doesn't affect the behavior.

Re: [Firebird-net-provider] Multithread insert

[Jiří Č. <ji...@ci...>]

On Thu, Sep 17, 2015, at 17:57, Геннадий Забула wrote:
> Narrowed the problem. The cause is a multithreaded update of the same
> record field. Transactions, as I said don't dispatch the issue.

The advice is simple. Don't update same record (not only in .NET;
anywhere, anytool). :D

-- 
Mgr. Jiří Činčura
Independent IT Specialist