RAD Studio VCL Reference
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TDBXIsolations Class
TDBXIsolations Constants | TDBXIsolations Members | Description | See Also
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Isolation levels supported by TDBXTransaction.

Class Hierarchy
Pascal
TDBXIsolations = class;
C++
class TDBXIsolations;
File

DBXCommon

Description

Isolation levels supported by the TDBXTransaction class. The isolation level indicates how much transactions can interact with each other. 

This table shows isolation levels constants.

Constant 
Description 
ReadCommitted  
Current transaction sees only changes that have been committed, but can receive an inconsistent view of the data if additional changes are committed before the transaction ends.  
RepeatableRead  
Current transaction is guaranteed a consistent view of the data, which includes only changes committed by other transactions at the start of the transaction.  
DirtyRead  
Current transaction sees all changes made by other transactions, even if they have not yet been committed. This option is not available for the Oracle driver.  
Serializable  
Available since dbExpress 4. Current transaction sees no changes made by other transactions including phantoms.  
SnapShot  
Available since dbExpress 4. Read only transaction that provides a transactionally consistent snapshot of the database.  

 

See Also
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