topic Exclusive Lock in Application Development and Automation Discussions

Exclusive Lock

Former Member — Fri, 03 Jan 2014 13:21:23 GMT

Hi All,

In which case exclusive locks can be requested several times from the same transaction.

In which situation required multiple time request to lock object in same transaction.

Re: Exclusive Lock

Former Member — Sat, 04 Jan 2014 01:55:19 GMT

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Re: Exclusive Lock

Former Member — Sat, 04 Jan 2014 06:30:38 GMT

Thanks Purushotham,

Form your thread also it is telling that exclusive locks can be requested several times from the same transaction.

My question is in which situation it is required to locks be requested several times from the same transaction.

Re: Exclusive Lock

Former Member — Sat, 04 Jan 2014 07:43:24 GMT

Hi Sandeep,

in exclusive lock we have two types.

1)exclusive -cumulative:( only one lock)

An exclusive lock protects the locked object against all types of locks from other transactions. Only the same lock owner can reset the lock (accumulate).

2)exclusive-non-cumulative:(several times from same user)

Exclusive locks can be requested several times from the same transaction and are processed successively. In contrast, exclusive but not cumulative locks can be called only once from the same transaction. Each further lock request will be rejected.

And your doubt is requested several times from the same transaction.

Here transaction means 'User' k.

And several times means ,we can keep the lock for part of the table also.

so if we want keep for same table exclusive non-cumulative will allow.

Regards,

Reddy.

Re: Exclusive Lock

Clemenss — Sat, 04 Jan 2014 11:08:11 GMT

to make it short:

locks requested several times from the same transaction

are never required but they don't hurt.

Sometimes you can't know if a required lock has already been set, so you just lockit, possibly again.

Regards

Clemens