TransactionIsolation (DataNucleus Core 4.1.17-SNAPSHOT API)

```
public interface TransactionIsolation
```
Definition of the transaction isolation levels considered by DataNucleus.

Field Summary

Fields
Modifier and Type	Field and Description
`static int`	`NONE` A constant indicating that transactions are not supported.
`static int`	`READ_COMMITTED` A constant indicating that dirty reads are prevented; non-repeatable reads and phantom reads can occur.
`static int`	`READ_UNCOMMITTED` A constant indicating that dirty reads, non-repeatable reads and phantom reads can occur.
`static int`	`REPEATABLE_READ` A constant indicating that dirty reads and non-repeatable reads are prevented; phantom reads can occur.
`static int`	`SERIALIZABLE` A constant indicating that dirty reads, non-repeatable reads and phantom reads are prevented.

- Field Detail
  - NONE
```
static final int NONE
```
    A constant indicating that transactions are not supported.
    
    See Also:
    
    Constant Field Values
  - READ_UNCOMMITTED
```
static final int READ_UNCOMMITTED
```
    A constant indicating that dirty reads, non-repeatable reads and phantom reads can occur. This level allows a row changed by one transaction to be read by another transaction before any changes in that row have been committed (a "dirty read"). If any of the changes are rolled back, the second transaction will have retrieved an invalid row.
    
    See Also:
    
    Constant Field Values
  - READ_COMMITTED
```
static final int READ_COMMITTED
```
    A constant indicating that dirty reads are prevented; non-repeatable reads and phantom reads can occur. This level only prohibits a transaction from reading a row with uncommitted changes in it.
    
    See Also:
    
    Constant Field Values
  - REPEATABLE_READ
```
static final int REPEATABLE_READ
```
    A constant indicating that dirty reads and non-repeatable reads are prevented; phantom reads can occur. This level prohibits a transaction from reading a row with uncommitted changes in it, and it also prohibits the situation where one transaction reads a row, a second transaction alters the row, and the first transaction rereads the row, getting different values the second time (a "non-repeatable read").
    
    See Also:
    
    Constant Field Values
  - SERIALIZABLE
```
static final int SERIALIZABLE
```
    A constant indicating that dirty reads, non-repeatable reads and phantom reads are prevented. This level includes the prohibitions in TRANSACTION_REPEATABLE_READ and further prohibits the situation where one transaction reads all rows that satisfy a WHERE condition, a second transaction inserts a row that satisfies that WHERE condition, and the first transaction rereads for the same condition, retrieving the additional "phantom" row in the second read.
    
    See Also:
    
    Constant Field Values

Interface TransactionIsolation

Field Summary

Field Detail

NONE

READ_UNCOMMITTED

READ_COMMITTED

REPEATABLE_READ

SERIALIZABLE