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TransactionIsolationLevel Enum

Definition

Enumerates the set of possible isolation levels for a Transaction.

public enum TransactionIsolationLevel
type TransactionIsolationLevel = 
Public Enum TransactionIsolationLevel
Inheritance
TransactionIsolationLevel

Fields

Name Value Description
Default 0

Indicates the default isolation level of the store.

ReadUncommitted 1

Indicates that volatile data can be read during the transaction.

ReadCommitted 2

Indicates that volatile data cannot be read during the transaction, but can be modified. Shared locks are held while data is being read to avoid dirty reads, but data can be changed before the end of the transaction that results in non-repeatable reads or phantom data.

RepeatableRead 3

Indicates that volatile data can be read but not modified during the transaction. Locks are placed on all data that is used in a query to prevent other users from updating data. New rows can be inserted into data sets and are included in later reads in the current transaction.

Snapshot 4

Indicates the snapshot level where volatile data can be read. Any data that is read will be a transaction-consistent version of the data that existed at start of the transaction.

Serializable 5

Indicates that volatile data are serializable. Volatile data can be read but not modified, and no new data can be added during the transaction. Indicates that range locks will be put on data sets. The locks prevent updates or inserts in data sets until the transaction finishes.

Applies to