.
A RASHOD . RASHOD B. , A, . C RASHOD . :
B , A ?
C , A B?
A , B, ?
() .
Dirty Read ( ) , , . , . .
Read Committed ( ) , A. , A , , .
Repetable Read ( ) () . A - , , ReadCommited, . , , A , , .. A . , , . , , , .
.
| Oracle | Dirty Read Read Committed Repetable Read | Read Committed Read Committed Repetable Read |
| MS SQL Server, Sybase | Dirty Read Read Committed Repetable Read | Read Committed Read Committed |
| DB2 | Dirty Read Read Committed Repetable Read | Dirty Read Read Committed Repetable Read |
| Informix | Dirty Read Read Committed Repetable Read | Dirty Read Read Committed Repetable Read |
| InterBase | Dirty Read Read Committed Repetable Read | Read Committed Read Committed Repetable Read |
| Dirty Read Read Committed Repetable Read | Dirty Read |
|
|
|
InterBase :
SET TRANSACTION [ ]
[READ WRITE | READ ONLY]
[WAIT | NO WAIT]
[[ISOLATION LEVEL] {SNAPSHOT [TABLE STABILITY]
| READ COMMITTED [[NO] RECORD_VERSION]}]
------------------------------
READ WRITE | READ ONLY WAIT ( READ WRITE)
WAIT | NO WAIT , : WAIT ( ) ; NO WAIT .
ISOLATION LEVEL ( SNAPSHOT, REPETABLE READ.
READ COMMITTED : NO RECORD_VERSION ( ) , ; WAIT, ; RECORD VERSION .
.
SET TRANSACTION WAIT
ISOLATION LEVEL READ COMMITTED
