Σημείωση
Η πρόσβαση σε αυτή τη σελίδα απαιτεί εξουσιοδότηση. Μπορείτε να δοκιμάσετε να συνδεθείτε ή να αλλάξετε καταλόγους.
Η πρόσβαση σε αυτή τη σελίδα απαιτεί εξουσιοδότηση. Μπορείτε να δοκιμάσετε να αλλάξετε καταλόγους.
Applies to:
SQL Server
Azure SQL Database
Azure SQL Managed Instance
Azure Synapse Analytics
Analytics Platform System (PDW)
SQL analytics endpoint in Microsoft Fabric
Warehouse in Microsoft Fabric
SQL database in Microsoft Fabric
Returns one row per authenticated session on SQL Server. sys.dm_exec_sessions is a server-scope view that shows information about all active user connections and internal tasks. This information includes client version, client program name, client login time, login user, current session setting, and more. Use sys.dm_exec_sessions to first view the current system load and to identify a session of interest, and then learn more information about that session by using other dynamic management views or dynamic management functions.
The sys.dm_exec_connections, sys.dm_exec_sessions, and sys.dm_exec_requests dynamic management views map to the deprecated sys.sysprocesses system compatibility view.
Note
To call this view from Azure Synapse Analytics (dedicated SQL pool only) or Analytics Platform System (PDW), see sys.dm_pdw_nodes_exec_sessions. Use sys.dm_exec_sessions for Azure Synapse Analytics (serverless SQL pool only) or Microsoft Fabric.
| Column name | Data type | Nullable | Description |
|---|---|---|---|
session_id |
smallint | No | Identifies the session associated with each active primary connection. |
login_time |
datetime | No | Time when session was established. Sessions that haven't completely logged in at the time this DMV is queried, are shown with a login time of 1900-01-01. |
host_name |
nvarchar(128) | Yes | Name of the client workstation that's specific to a session. The value is NULL for internal sessions.Security note: The client application provides the workstation name and can provide inaccurate data. Don't rely on HOST_NAME as a security feature. |
program_name |
nvarchar(128) | Yes | Name of client program that initiated the session. The value is NULL for internal sessions. |
host_process_id |
int | Yes | Process ID of the client program that initiated the session. The value is NULL for internal sessions. |
client_version |
int | Yes | TDS protocol version of the interface used by the client to connect to the server. The value is NULL for internal sessions. |
client_interface_name |
nvarchar(32) | Yes | Name of library/driver being used by the client to communicate with the server. The value is NULL for internal sessions. |
security_id |
varbinary(85) | No | Windows security ID associated with the login. |
login_name |
nvarchar(128) | No | SQL Server login name under which the session is currently executing. For the original login name that created the session, see original_login_name. Can be a SQL Server authenticated login name or a Windows authenticated domain user name. |
nt_domain |
nvarchar(128) | Yes | Windows domain for the client if the session is using Windows Authentication or a trusted connection. This value is NULL for internal sessions and non-domain users. |
nt_user_name |
nvarchar(128) | Yes | Windows user name for the client if the session is using Windows Authentication or a trusted connection. This value is NULL for internal sessions and non-domain users. |
status |
nvarchar(30) | No | Status of the session. Possible values:Running - Currently running one or more requestsSleeping - Currently running no requestsDormant - Session was reset because of connection pooling and is now in prelogin state.Preconnect - Session is in the Resource Governor classifier. |
context_info |
varbinary(128) | Yes | CONTEXT_INFO value for the session. The context information is set by the user by using the SET CONTEXT_INFO statement. |
cpu_time |
int | No | CPU time, in milliseconds, used by this session. |
memory_usage |
int | No | Number of 8-KB pages of memory used by this session. |
total_scheduled_time |
int | No | Total time, in milliseconds, for which the session (requests within) were scheduled for execution. |
total_elapsed_time |
int | No | Time, in milliseconds, since the session was established. |
endpoint_id |
int | No | ID of the endpoint associated with the session. |
last_request_start_time |
datetime | No | Time at which the last request on the session began. This time includes the currently executing request. |
last_request_end_time |
datetime | Yes | Time of the last completion of a request on the session. |
reads |
bigint | No | Number of physical reads performed, by requests in this session, during this session. |
writes 1 |
bigint | No | Number of physical writes performed, by requests in this session, during this session. |
logical_reads |
bigint | No | Number of logical reads performed, by requests in this session, during this session. |
is_user_process |
bit | No | 0 if the session is a system session. Otherwise, it's 1. |
text_size |
int | No | TEXTSIZE setting for the session. |
language |
nvarchar(128) | Yes | LANGUAGE setting for the session. |
date_format |
nvarchar(3) | Yes | DATEFORMAT setting for the session. |
date_first |
smallint | No | DATEFIRST setting for the session. |
quoted_identifier |
bit | No | QUOTED_IDENTIFIER setting for the session. |
arithabort |
bit | No | ARITHABORT setting for the session. |
ansi_null_dflt_on |
bit | No | ANSI_NULL_DFLT_ON setting for the session. |
ansi_defaults |
bit | No | ANSI_DEFAULTS setting for the session. |
ansi_warnings |
bit | No | ANSI_WARNINGS setting for the session. |
ansi_padding |
bit | No | ANSI_PADDING setting for the session. |
ansi_nulls |
bit | No | ANSI_NULLS setting for the session. |
concat_null_yields_null |
bit | No | CONCAT_NULL_YIELDS_NULL setting for the session. |
transaction_isolation_level |
smallint | No | Transaction isolation level of the session.0 = Unspecified1 = ReadUncommitted2 = ReadCommitted3 = RepeatableRead4 = Serializable5 = Snapshot |
lock_timeout |
int | No | LOCK_TIMEOUT setting for the session. The value is in milliseconds. |
deadlock_priority |
int | No | DEADLOCK_PRIORITY setting for the session. |
row_count |
bigint | No | Number of rows returned on the session up to this point. |
prev_error |
int | No | ID of the last error returned on the session. |
original_security_id |
varbinary(85) | No | Windows security ID that is associated with the original_login_name. |
original_login_name |
nvarchar(128) | No | SQL Server login name that the client used to create this session. Can be a SQL Server authenticated login name, a Windows authenticated domain user name, or a contained database user. The session might have been through many implicit or explicit context switches after the initial connection, for example, if EXECUTE AS is used. |
last_successful_logon |
datetime | Yes | Time of the last successful logon for the original_login_name before the current session started. |
last_unsuccessful_logon |
datetime | Yes | Time of the last unsuccessful logon attempt for the original_login_name before the current session started. |
unsuccessful_logons |
bigint | Yes | Number of unsuccessful logon attempts for the original_login_name between the last_successful_logon and login_time. |
group_id |
int | No | ID of the workload group to which this session belongs. |
database_id |
smallint | No | ID of the current database for each session. In Azure SQL Database, the values are unique within a single database or an elastic pool, but not within a logical server. Applies to: SQL Server 2012 (11.x) and later versions. |
authenticating_database_id |
int | Yes | ID of the database authenticating the principal. For logins, the value is 0. For contained database users, the value is the database ID of the contained database.Applies to: SQL Server 2012 (11.x) and later versions. |
open_transaction_count |
int | No | Number of open transactions per session. Applies to: SQL Server 2012 (11.x) and later versions. |
pdw_node_id |
int | No | The identifier for the node that this distribution is on. Applies to: Azure Synapse Analytics, and Analytics Platform System (PDW). |
page_server_reads |
bigint | No | Number of page server reads performed, by requests in this session, during this session. Applies to: Azure SQL Database Hyperscale. |
contained_availability_group_id |
uniqueidentifier | Yes | ID of the contained availability group. Applies to: SQL Server 2025 (17.x) and later versions. |
1 Specifies when a page is marked dirty in the buffer pool. This value doesn't directly equate to actual writes, because the same page can be marked more than once. These counters are aggregated at the end of the batch.
Permissions
Everyone can see their own session information.
In SQL Server 2019 (15.x) and earlier versions, requires VIEW SERVER STATE to see all sessions on the server. In SQL Server 2022 (16.x) and later versions, requires VIEW SERVER PERFORMANCE STATE permission on the server.
In SQL Database, requires VIEW DATABASE STATE to see all connections to the current database. VIEW DATABASE STATE can't be granted in the master database.
Remarks
When the common criteria compliance enabled server configuration option is enabled, logon statistics are displayed in the following columns.
last_successful_logonlast_unsuccessful_logonunsuccessful_logons
If this option isn't enabled, these columns return null values. For more information about how to set this server configuration option, see Enable common criteria compliance configuration.
The admin connections on Azure SQL Database see one row per authenticated session. The sa sessions that appear in the resultset, don't have any effect on the user quota for sessions. The non-admin connections only see information related to their database user sessions.
Because of differences in how they're recorded, open_transaction_count might not match sys.dm_tran_session_transactions.open_transaction_count.
Relationship cardinalities
| From | To | On/Apply | Relationship |
|---|---|---|---|
sys.dm_exec_sessions |
sys.dm_exec_requests | session_id |
One-to-zero or one-to-many |
sys.dm_exec_sessions |
sys.dm_exec_connections | session_id |
One-to-zero or one-to-many |
sys.dm_exec_sessions |
sys.dm_tran_session_transactions | session_id |
One-to-zero or one-to-many |
sys.dm_exec_sessions |
sys.dm_exec_cursors (session_id | 0) |
session_id CROSS APPLYOUTER APPLY |
One-to-zero or one-to-many |
sys.dm_exec_sessions |
sys.dm_db_session_space_usage | session_id |
One-to-one |
Examples
A. Find users that are connected to the server
The following example finds the users that are connected to the server and returns the number of sessions for each user.
SELECT login_name,
COUNT(session_id) AS session_count
FROM sys.dm_exec_sessions
GROUP BY login_name;
B. Find long-running cursors
The following example finds the cursors that were open for more than a specific period of time, who created the cursors, and what session the cursors are on.
USE master;
GO
SELECT creation_time,
cursor_id,
name,
c.session_id,
login_name
FROM sys.dm_exec_cursors(0) AS c
INNER JOIN sys.dm_exec_sessions AS s
ON c.session_id = s.session_id
WHERE DATEDIFF(mi, c.creation_time, GETDATE()) > 5;
C. Find idle sessions that have open transactions
The following example finds sessions that have open transactions and are idle. An idle session is one that has no request currently running.
SELECT s.*
FROM sys.dm_exec_sessions AS s
WHERE EXISTS (SELECT *
FROM sys.dm_tran_session_transactions AS t
WHERE t.session_id = s.session_id)
AND NOT EXISTS (SELECT *
FROM sys.dm_exec_requests AS r
WHERE r.session_id = s.session_id);
D. Find information about a query's own connection
The following example gathers information about a query's own connection:
SELECT c.session_id,
c.net_transport,
c.encrypt_option,
c.auth_scheme,
s.host_name,
s.program_name,
s.client_interface_name,
s.login_name,
s.nt_domain,
s.nt_user_name,
s.original_login_name,
c.connect_time,
s.login_time
FROM sys.dm_exec_connections AS c
INNER JOIN sys.dm_exec_sessions AS s
ON c.session_id = s.session_id
WHERE c.session_id = @@SPID;