I have been reading about SQL Server Audit, and so far I have assimilated that it tracks the command that has been executed, and some other additional information(SPID, object ID and stuff). But can this be used to uniquely identify the individual that did it, or some type of unique ID of the computer from which the command was executed, such as host name or IP address?

I just do not want to waste my time reading it if it can not uniquely identify the machine or the person executing the command.

3 Answers 3


With SQLAudit you cannot track HostName or IP address.

However, there's an alternative method for auditing, based on streaming extended events. I blogged about it earlier this year.

Basically, you treat locks acquired as indicators of the operations being performed on the tables (shared locks and schema stability locks for reads and exclusive locks for writes) and you capture these events with an extended events session. You will need to hook a script (or an executable) to that session using the streaming API and you can implement your own logic to filter, categorize and persist the events you're interested in.

Another possibility is capturing the "Audit Schema Object Access Event" events with a trace and streaming them to your own custom application. Here's a tutorial. In Extended Events the same event is not available, as it is reserved for the SQLAudit implementation.

  • This is sort of costly, creating an Event Session for every event, the production server will take a hit Commented Sep 4, 2015 at 15:37
  • 1
    Actually the higher cost is on the side of the application that receives the events rather than on the event session itself. I tried it against a rather busy server and I can confirm my findings. Commented Sep 4, 2015 at 15:50
  • @spaghettidba I have been experimenting with your Extended Events code, that employs the principal of tracking by locks acquired. However, i have some system jobs(CDC jobs) running that also get logged in this process. How do i filter them out and track only for users and not system? Commented Sep 17, 2015 at 9:10

To be honest, the SQL Auditing features are pretty poor considering the functionality has been around since 2008. I cannot believe that the host name and application name are not captured as 'normal' fields. Anyway here is a solution that I came up with which basically retrieves the related login record, extracts its hostname (app name not available) and then updates the select records hostname with the data. It then removes all of the unwanted login records.

IF EXISTS (SELECT 1 FROM sys.tables WHERE name = 'AuditLog')
   DROP TABLE dbo.AuditLog

CREATE TABLE dbo.AuditLog(
    event_time DATETIME2(7) NOT NULL,
    sequence_number INT NOT NULL,
    action_id VARCHAR(4) NOT NULL DEFAULT '',
    succeeded BIT NOT NULL,
    permission_bitmask VARBINARY(16) NOT NULL,
    is_column_permission BIT NOT NULL,
    session_id SMALLINT NOT NULL,
    server_principal_id INT NOT NULL,
    database_principal_id INT NOT NULL,
    target_server_principal_id INT NOT NULL,
    target_database_principal_id INT NOT NULL,
    object_id INT NOT NULL,
    class_type VARCHAR(2) NULL,
    session_server_principal_name NVARCHAR(128) NULL,
    server_principal_name NVARCHAR(128) NULL,
    server_principal_sid VARBINARY(85) NULL,
    database_principal_name NVARCHAR(128) NULL,
    target_server_principal_name NVARCHAR(128) NULL,
    target_server_principal_sid VARBINARY(85) NULL,
    target_database_principal_name NVARCHAR(128) NULL,
    server_instance_name NVARCHAR(128) NULL,
    database_name NVARCHAR(128) NULL,
    schema_name NVARCHAR(128) NULL,
    object_name NVARCHAR(128) NULL,
    statement NVARCHAR(4000) NULL,
    additional_information XML NULL,
    file_name NVARCHAR(260) NOT NULL,
    audit_file_offset BIGINT NOT NULL,
    user_defined_event_id SMALLINT NOT NULL,
    user_defined_information NVARCHAR(4000) NULL,
    audit_schema_version INT NOT NULL,
    sequence_group_id VARBINARY(85) NOT NULL,
    transaction_id BIGINT NOT NULL,
    host_name NVARCHAR(255) NULL,
    related_login_event_time DATETIME2(7) NULL
    CONSTRAINT PKAuditLog PRIMARY KEY CLUSTERED (event_time, action_id, session_id, sequence_group_id)



INSERT  dbo.AuditLog
        ( event_time ,
          sequence_number ,
          action_id ,
          succeeded ,
          permission_bitmask ,
          is_column_permission ,
          session_id ,
          server_principal_id ,
          database_principal_id ,
          target_server_principal_id ,
          target_database_principal_id ,
          object_id ,
          class_type ,
          session_server_principal_name ,
          server_principal_name ,
          server_principal_sid ,
          database_principal_name ,
          target_server_principal_name ,
          target_server_principal_sid ,
          target_database_principal_name ,
          server_instance_name ,
          database_name ,
          schema_name ,
          object_name ,
          statement ,
          additional_information ,
          file_name ,
          audit_file_offset ,
          user_defined_event_id ,
          user_defined_information ,
          audit_schema_version ,
          sequence_group_id ,
        SELECT  fgaf.event_time ,
                fgaf.sequence_number ,
                fgaf.action_id ,
                fgaf.succeeded ,
                fgaf.permission_bitmask ,
                fgaf.is_column_permission ,
                fgaf.session_id ,
                fgaf.server_principal_id ,
                fgaf.database_principal_id ,
                fgaf.target_server_principal_id ,
                fgaf.target_database_principal_id ,
                fgaf.object_id ,
                fgaf.class_type ,
                fgaf.session_server_principal_name ,
                fgaf.server_principal_name ,
                fgaf.server_principal_sid ,
                fgaf.database_principal_name ,
                fgaf.target_server_principal_name ,
                fgaf.target_server_principal_sid ,
                fgaf.target_database_principal_name ,
                fgaf.server_instance_name ,
                fgaf.database_name ,
                fgaf.schema_name ,
                fgaf.object_name ,
                fgaf.statement ,
                fgaf.additional_information ,
                fgaf.file_name ,
                fgaf.audit_file_offset ,
                fgaf.user_defined_event_id ,
                fgaf.user_defined_information ,
                fgaf.audit_schema_version ,
                fgaf.sequence_group_id ,
        FROM    sys.fn_get_audit_file('c:\ESD\PMAudit*', DEFAULT, DEFAULT) AS fgaf
                             FROM   dbo.AuditLog al
                             WHERE  al.event_time = fgaf.event_time
                                    AND al.action_id = fgaf.action_id
                                    AND al.session_id = fgaf.session_id
                                    AND al.sequence_group_id = fgaf.sequence_group_id )
                AND fgaf.action_id <> 'AUSC';

CREATE PROCEDURE dbo.AuditLog_Insert

      event_time DATETIME2(7) NOT NULL ,
      session_id SMALLINT NOT NULL ,
      server_principal_name NVARCHAR(128) NOT NULL ,
      sequence_group_id VARBINARY(85) NOT NULL, 
      host_name NVARCHAR(50) NULL ,
      session_seq BIGINT NOT NULL ,
      CONSTRAINT PKLogins PRIMARY KEY CLUSTERED (event_time, session_id, server_principal_name, sequence_group_id)

;WITH XMLNAMESPACES('http://schemas.microsoft.com/sqlserver/2008/sqlaudit_data' AS ns)
INSERT #Logins
        ( event_time ,
          session_id ,
          server_principal_name ,
          sequence_group_id ,
          host_name ,
          session_seq --Required as its possible to get duplicate event_time + session_id + server_principle_name combinations
SELECT   a.event_time ,
         a.session_id ,
         a.server_principal_name ,
         sequence_group_id ,
         t.c.value ('ns:address[1]', 'varchar(50)') AS host_name,
         ROW_NUMBER() OVER ( PARTITION BY a.event_time,
                                            a.server_principal_name, t.c.value ('ns:address[1]', 'varchar(50)')  ORDER BY a.event_time DESC ) AS session_seq
FROM     dbo.AuditLog a
OUTER APPLY a.additional_information.nodes('//ns:action_info') AS t(c)
WHERE a.action_id = 'LGIS'

--Update the Select records with the host_name from login detail records .. using max event_time for that session
SET     al.host_name = l.host_name,
        al.related_login_event_time = l.event_time
FROM    dbo.AuditLog AS al
        JOIN #Logins l ON l.session_id = al.session_id
                       AND l.server_principal_name = al.server_principal_name
                       AND l.event_time = ( SELECT MAX(l2.event_time)
                                            FROM   #Logins AS l2
                                            WHERE  l2.event_time < al.event_time
                                            AND    l2.session_id = al.session_id
                                            AND    l2.server_principal_name = al.server_principal_name)

WHERE   al.action_id = 'SL'
        AND l.session_seq = 1 --It is possible to have duplicates because of horrible way SSMS operates
        AND al.host_name IS NULL -- Dont update records that have already been populated

--Remove unwanted login records from the Audit Log ... leaving only those related to select records.  Otherwise we are left with many duplicated login records.                 ;
FROM    AuditLog al
WHERE   al.action_id = 'LGIS'
                         FROM   dbo.AuditLog al1
                         WHERE  al1.action_id = 'SL'
                                AND al1.related_login_event_time = al.event_time )


I haven't done it myself but as I understand it you can create a login/out audit specification (these events do pull hostname) and then tie that information to other audit results using the SPID and rundate / login/out date information.

If I have time I'll try to come back later with more specifics.

  • Nope, login/logout audit specification do not furnish you with the host name. I'm resorting to the Extended Events feature, it's doing the trick for me! Commented Sep 11, 2015 at 8:25

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