Re: [sqlite] sqlite3_step returns sqlite_busy

[Pavel Ivanov]

> So it means we can have mor than one valid db handle?

Yes.

Pavel

On Wed, Jul 7, 2010 at 9:29 AM, Lloyd <ll...@cdactvm.in> wrote:
> So it means we can have mor than one valid db handle?
>
> Thanks,
>  Lloyd
>
> - Original Message -
> From: "Pavel Ivanov" <paiva...@gmail.com>
> To: "General Discussion of SQLite Database" <sqlite-users@sqlite.org>
> Sent: Wednesday, July 07, 2010 6:40 PM
> Subject: Re: [sqlite] sqlite3_step returns sqlite_busy
>
>
>>> one thread is preparing an "INSERT" statement (It returns SQLITE_OK),
>>> then it is executed using sqlite3_step. sqlite3_step returns an
>>> SQLITE_BUSY! Is there any possibility for this?
>>
>> Sure. Preparing INSERT statement doesn't acquire any "write" locks on
>> the database. It's executing the INSERT statement that acquires locks.
>> So if while executing statement finds that it can't get the locks then
>> sqlite3_step returns SQLITE_BUSY. And thread-safety is irrelevant
>> here.
>>
>>
>> Pavel
>>
>
>
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Re: [sqlite] sqlite3_step returns sqlite_busy

[Lloyd]

So it means we can have mor than one valid db handle?

Thanks,
  Lloyd

- Original Message - 
From: "Pavel Ivanov" <paiva...@gmail.com>
To: "General Discussion of SQLite Database" <sqlite-users@sqlite.org>
Sent: Wednesday, July 07, 2010 6:40 PM
Subject: Re: [sqlite] sqlite3_step returns sqlite_busy


>> one thread is preparing an "INSERT" statement (It returns SQLITE_OK),
>> then it is executed using sqlite3_step. sqlite3_step returns an
>> SQLITE_BUSY! Is there any possibility for this?
> 
> Sure. Preparing INSERT statement doesn't acquire any "write" locks on
> the database. It's executing the INSERT statement that acquires locks.
> So if while executing statement finds that it can't get the locks then
> sqlite3_step returns SQLITE_BUSY. And thread-safety is irrelevant
> here.
> 
> 
> Pavel
> 


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Re: [sqlite] sqlite3_step returns sqlite_busy

[Pavel Ivanov]

> one thread is preparing an "INSERT" statement (It returns SQLITE_OK),
> then it is executed using sqlite3_step. sqlite3_step returns an
> SQLITE_BUSY! Is there any possibility for this?

Sure. Preparing INSERT statement doesn't acquire any "write" locks on
the database. It's executing the INSERT statement that acquires locks.
So if while executing statement finds that it can't get the locks then
sqlite3_step returns SQLITE_BUSY. And thread-safety is irrelevant
here.


Pavel

On Wed, Jul 7, 2010 at 7:56 AM, Lloyd  wrote:
> Hi,
>
> We have a multi-threaded application (I know "threads are evil", but this is 
> a small server application). Each thread tries to access the SQLite database. 
> When trying to get a DB handle (sqlite3_open), if it returns SQLITE_BUSY, 
> then the thread will wait for some time and try to open it again (until it 
> gets the handle). In our case, two threads are running, one thread is 
> preparing an "INSERT" statement (It returns SQLITE_OK), then it is executed 
> using sqlite3_step. sqlite3_step returns an SQLITE_BUSY! Is there any 
> possibility for this? ( I think these two threads are obtaining the DB handle 
> at the same time using sqlite_open - with wrtie permission- is it possible?) 
> I have tried compiling the application with both  -DSQLITE_THREADSAFE=2 and 
> -DSQLITE_THREADSAFE=1.
>
> Any hint would be very helpful...
>
> Thanks a lot,
>  Lloyd
>
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[sqlite] sqlite3_step returns sqlite_busy

[Lloyd]

Hi,

We have a multi-threaded application (I know "threads are evil", but this is a 
small server application). Each thread tries to access the SQLite database. 
When trying to get a DB handle (sqlite3_open), if it returns SQLITE_BUSY, then 
the thread will wait for some time and try to open it again (until it gets the 
handle). In our case, two threads are running, one thread is preparing an 
"INSERT" statement (It returns SQLITE_OK), then it is executed using 
sqlite3_step. sqlite3_step returns an SQLITE_BUSY! Is there any possibility for 
this? ( I think these two threads are obtaining the DB handle at the same time 
using sqlite_open - with wrtie permission- is it possible?) I have tried 
compiling the application with both  -DSQLITE_THREADSAFE=2 and 
-DSQLITE_THREADSAFE=1.

Any hint would be very helpful...

Thanks a lot,
  Lloyd

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