SqlIsolationLevel Enum

Lists values that specify the isolation level under which a Transact-SQL statement determines its locking and row versioning behavior.

Namespace: DevExpress.DataAccess.Sql

Assembly: DevExpress.DataAccess.v24.2.dll

NuGet Package: DevExpress.DataAccess

Declaration

C#

[ResourceFinder(typeof(ResFinder))]
public enum SqlIsolationLevel : byte

VB.NET

<ResourceFinder(GetType(ResFinder))>
Public Enum SqlIsolationLevel As Byte

Members

Name	Description
None	The default isolation level of the database management system is used.
ReadUncommitted	A transaction retrieves data that has been modified but not committed by other transactions.
ReadCommitted	Transaction statements cannot read data that has been modified but not committed by other transactions.
RepeatableRead	Transaction statements cannot read data that has been modified but not yet committed by other transactions. Other transactions cannot modify data that has been read by the current transaction until the current transaction is completed.
Serializable	A transaction retrieves exactly the same data every time it repeats a read operation.
Snapshot	Specifies that data read by any statement in a transaction will be the transactionally consistent version of data that existed at the start of the transaction.

Related API Members

The following properties accept/return SqlIsolationLevel values:

• ConnectionOptions.IsolationLevel
• SqlQuery.IsolationLevel

Remarks

An SQL transaction is a grouping of one or more SQL statements (queries) that interact with a database. Transactions specify an isolation level that defines how one transaction is isolated from other transactions. Isolation is the separation of resource or data modifications made by different transactions.

Isolation Levels apply to all SQL providers. Refer to the the Microsoft help documentation for more information about different provider specifics. For example, Transaction Isolation Levels for MS SQl Server.