Friday, March 30, 2012

Locking

Hi all!
Can anyone point me to a doc that describes what the default locking levels
were across different versions of SQL, i.e. row vs. page vs. table, going
all the way back to version 4.2, and what the circumstances would have been
when SQL decides what to use over the other? Guess versions 4.2 and 6.x were
page-locking no matter what if I remember correctly, but want to make sure
before I tell my colleagues rubbish.
Thanks in advance,
Jan Van der Eecken
I don't have any documentation but you didn't have true row level locks
until version 7.0. So before that it was Page and after it is Row.
Andrew J. Kelly SQL MVP
"Jan Van der Eecken" <jvandereecken@.omam.com> wrote in message
news:u$lROWbWGHA.1228@.TK2MSFTNGP02.phx.gbl...
> Hi all!
> Can anyone point me to a doc that describes what the default locking
> levels were across different versions of SQL, i.e. row vs. page vs. table,
> going all the way back to version 4.2, and what the circumstances would
> have been when SQL decides what to use over the other? Guess versions 4.2
> and 6.x were page-locking no matter what if I remember correctly, but want
> to make sure before I tell my colleagues rubbish.
> Thanks in advance,
> Jan Van der Eecken
>
|||Thanks Andrew. I was almost under the impression that it was page-level in
7.0 as well.
Cheers,
Jan
"Andrew J. Kelly" <sqlmvpnooospam@.shadhawk.com> wrote in message
news:%23LP5XxdWGHA.2376@.TK2MSFTNGP03.phx.gbl...
>I don't have any documentation but you didn't have true row level locks
>until version 7.0. So before that it was Page and after it is Row.
> --
> Andrew J. Kelly SQL MVP
>
> "Jan Van der Eecken" <jvandereecken@.omam.com> wrote in message
> news:u$lROWbWGHA.1228@.TK2MSFTNGP02.phx.gbl...
>
|||6.5 added some possibility to get some type of row locks for INSERTs. Sorry to be vague, but it was
a long time ago. As I recall, you had to satisfy a number of conditions (probably what indexes you
had) in order to get some concurrency on the page for INSERT operations.
Tibor Karaszi, SQL Server MVP
http://www.karaszi.com/sqlserver/default.asp
http://www.solidqualitylearning.com/
Blog: http://solidqualitylearning.com/blogs/tibor/
"Andrew J. Kelly" <sqlmvpnooospam@.shadhawk.com> wrote in message
news:%23LP5XxdWGHA.2376@.TK2MSFTNGP03.phx.gbl...
>I don't have any documentation but you didn't have true row level locks until version 7.0. So
>before that it was Page and after it is Row.
> --
> Andrew J. Kelly SQL MVP
>
> "Jan Van der Eecken" <jvandereecken@.omam.com> wrote in message
> news:u$lROWbWGHA.1228@.TK2MSFTNGP02.phx.gbl...
>
|||Thanks, Tibor
"Tibor Karaszi" <tibor_please.no.email_karaszi@.hotmail.nomail.com> wrote in
message news:%23dwfZahWGHA.4620@.TK2MSFTNGP04.phx.gbl...
> 6.5 added some possibility to get some type of row locks for INSERTs.
> Sorry to be vague, but it was a long time ago. As I recall, you had to
> satisfy a number of conditions (probably what indexes you had) in order to
> get some concurrency on the page for INSERT operations.
> --
> Tibor Karaszi, SQL Server MVP
> http://www.karaszi.com/sqlserver/default.asp
> http://www.solidqualitylearning.com/
> Blog: http://solidqualitylearning.com/blogs/tibor/
>
> "Andrew J. Kelly" <sqlmvpnooospam@.shadhawk.com> wrote in message
> news:%23LP5XxdWGHA.2376@.TK2MSFTNGP03.phx.gbl...
>

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