sys.syslockinfo (Transact-SQL)

rsc_text

nchar(32)

Textual description of a lock resource. Contains a part of the resource name.

rsc_valblk

binary(16)

Lock value block. Some resource types may include additional data in the lock resource that is not hashed by the lock manager to determine ownership of a particular lock resource. For example, page locks are not owned by a particular object ID. For lock escalation and other purposes. However, the object ID of a page lock may be included in the lock value block.

rsc_indid

smallint

Index ID associated with the resource, if appropriate.

rsc_type

tinyint

Resource type:

1 = NULL Resource (not used)

2 = Database

3 = File

4 = Index

5 = Table

6 = Page

7 = Key

8 = Extent

9 = RID (Row ID)

10 = Application

req_mode

tinyint

Lock request mode. This column is the lock mode of the requester and represents either the granted mode, or the convert or waiting mode.

0 = NULL. No access is granted to the resource. Serves as a placeholder.

1 = Sch-S (Schema stability). Ensures that a schema element, such as a table or index, is not dropped while any session holds a schema stability lock on the schema element.

2 = Sch-M (Schema modification). Must be held by any session that wants to change the schema of the specified resource. Ensures that no other sessions are referencing the indicated object.

3 = S (Shared). The holding session is granted shared access to the resource.

4 = U (Update). Indicates an update lock acquired on resources that may eventually be updated. It is used to prevent a common form of deadlock that occurs when multiple sessions lock resources for potential update in the future.

5 = X (Exclusive). The holding session is granted exclusive access to the resource.

6 = IS (Intent Shared). Indicates the intention to place S locks on some subordinate resource in the lock hierarchy.

7 = IU (Intent Update). Indicates the intention to place U locks on some subordinate resource in the lock hierarchy.

8 = IX (Intent Exclusive). Indicates the intention to place X locks on some subordinate resource in the lock hierarchy.

9 = SIU (Shared Intent Update). Indicates shared access to a resource with the intent of acquiring update locks on subordinate resources in the lock hierarchy.

10 = SIX (Shared Intent Exclusive). Indicates shared access to a resource with the intent of acquiring exclusive locks on subordinate resources in the lock hierarchy.

11 = UIX (Update Intent Exclusive). Indicates an update lock hold on a resource with the intent of acquiring exclusive locks on subordinate resources in the lock hierarchy.

12 = BU. Used by bulk operations.

13 = RangeS_S (Shared Key-Range and Shared Resource lock). Indicates serializable range scan.

14 = RangeS_U (Shared Key-Range and Update Resource lock). Indicates serializable update scan.

15 = RangeI_N (Insert Key-Range and Null Resource lock). Used to test ranges before inserting a new key into an index.

16 = RangeI_S. Key-Range Conversion lock, created by an overlap of RangeI_N and S locks.

17 = RangeI_U. Key-Range Conversion lock, created by an overlap of RangeI_N and U locks.

18 = RangeI_X. Key-Range Conversion lock, created by an overlap of RangeI_N and X locks.

19 = RangeX_S. Key-Range Conversion lock, created by an overlap of RangeI_N and RangeS_S. locks.

20 = RangeX_U. Key-Range Conversion lock, created by an overlap of RangeI_N and RangeS_U locks.

21 = RangeX_X (Exclusive Key-Range and Exclusive Resource lock). This is a conversion lock used when updating a key in a range.

req_refcnt

smallint

Lock reference count. Every time a transaction asks for a lock on a particular resource, a reference count is incremented. The lock cannot be released until the reference count equals 0.

req_lifetime

int

Lock lifetime bitmap. During certain query processing strategies, locks must be maintained on resources until the query processor has completed a particular phase of the query. The lock lifetime bitmap is used by the query processor and transaction manager to indicate groups of locks that can be released when a certain phase of a query has finished running. Certain bits in the bitmap are used to indicate locks that are held until the end of a transaction, even if their reference count equals 0.

req_ecid

int

Execution context ID (ECID). Used to indicate which thread in a parallel operation owns a particular lock.

req_transactionID

bigint

Unique transaction ID used in syslockinfo and in profiler event