record locks

[Ruslan Zasukhin]

On 5/28/04 12:55 PM, "mergault.olivier at wanadoo.fr"
<mergault.olivier at wanadoo.fr> wrote:

> Name:      Mergault Olivier
> 
> Question regarding: v4rb
> 
> V4RB Reference pdf is not very helpfull to understand how records are locked
> and
&#160;unlocked !Espacially for beginners !
> 
> So, how can one learn all about that essential point ?

Hi Mergault,

This is true that Valentina 1.x docs are short, and often require expert
level from developer. We try improve this in 2.0 docs.
 
You can read about record locks in ANY SQL book, I believe.

Actually all easy.

No locks -- no problems. No locks.

Read Lock. Or shared lock.
    You can set it if record do not have WRITE lock,
    several users can set READ lock on the same record.

WRITE LOCK, 
    you can set it if record do not have any other locks.
    

Cursor when is created, locks all selected records as you have specify.

If it cannot lock at least one record as required, then ALL fails, and you
get error Cannot set lock.

When cursor die, it unlock all records.


-- 
Best regards,
Ruslan Zasukhin      [ I feel the need...the need for speed ]
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e-mail: ruslan at paradigmasoft.com
web: http://www.paradigmasoft.com

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