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Topic: Record blocking

Forum List » AnyDAC » v 1.x General English

Mateusz
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Record blocking

Posted: 2008/02/11 05:00

Hello.

How can I block editing this same record by 2 and more users ??
I try use properties UpdateOptions of TAdConnection like LockMode, LockPoint and LockWait and I also write same LockSQL qurey for TAdUpdateSQL but it doesn't work.

Diman

Admin

Posts: 1460

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Re:Record blocking

Posted: 2008/02/11 07:47

Hello

1) How you setup UpdateOptions ?
2) Try to set:
UpdateOptions.LockMode = lmPessimistic
UpdateOptions.LockPoint = lpImmediate
UpdateOptions.LokcWait = True
3) Also what is your DBMS ?

Regards,
Dmitry

Mateusz
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Re:Record blocking

Posted: 2008/02/12 00:54

Hello

When i use this settings of UpdateOptions i get this message: "Update table undefined". Then I define LockSQL query for TAdUpdateSQL - I try empty update (something like: update table set id = :old_id where id = :old_id), but it doesn't work (different users can edit this record).

I use MySQL 5.0.

Greetings,
Mateusz

Diman

Admin

Posts: 1460

Karma: 18

Re:Record blocking

Posted: 2008/02/12 01:06

1) If you get "Update table undefined", it means anydac is unable to get table name. You can specifiy it in UpdateOptions.UpdateTableName.
2) LockSQL for MySQL should contain something like that:


 SELECT * FROM MyTab 
WHERE ID = :OLD_ID
LOCK IN SHARE MODE

And not an UPDATE command.
3) Pessimistic locking will work for InnoDB tables, for example. And will not for MyISAM.

Mateusz
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Posts: 3

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Re:Record blocking

Posted: 2008/02/12 02:09

Hello,

1) I define UpdateTableName,
2) I use this kind of query for LockSql,
3) I use InnoDB tables for MySql

but locking still doesn't work. Maybe I must set some other properties ?

Greetings,

Mateusz

Forum List » AnyDAC » v 1.x General English