SQL Server 2008 Audit trigger based on sub string - sql

Question

I would like to create a trigger based on a column but only for those records that end in _ess. How can I set up an audit trigger to do this?
Here is the current trigger but it just checks for all changes to username, whereas I just want it to check when username is updated to or from a username ending in _ess.
SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
CREATE TRIGGER [dbo].[AUDIT_UPD_HRPERSONS_USERNAME] ON [dbo].[HRPersons] FOR UPDATE NOT FOR REPLICATION As
BEGIN
DECLARE
#OperationNum int,
#DBMSTransaction VARCHAR(255),
#OSUSER VARCHAR(50),
#DBMSUSER VARCHAR(50),
#HostPhysicalAddress VARCHAR(17),
#contexto varchar(128),
#ApplicationModifierUser varchar(50),
#SessionInfo_OSUser varchar(50),
#HostLogicalAddress varchar(30)
Set NOCOUNT On
IF ##trancount>0
BEGIN
EXECUTE sp_getbindtoken #DBMSTransaction OUTPUT
END
ELSE BEGIN
SET #DBMSTransaction = NULL
END
IF PatIndex( '%\%',SUSER_SNAME()) > 0
BEGIN
set #OSUSER = SUSER_SNAME()
set #DBMSUSER = NULL
END
ELSE BEGIN
SET #OSUSER = NULL
SET #DBMSUSER = SUSER_SNAME()
END
set #HostPhysicalAddress = (SELECT net_address FROM master..sysprocesses where spid=##spid )
set #HostPhysicalAddress = substring (#HostPhysicalAddress,1,2) + '-' + substring (#HostPhysicalAddress,3,2) + '-' + substring (#HostPhysicalAddress,5,2) + '-' + substring (#HostPhysicalAddress,7,2) + '-' + substring (#HostPhysicalAddress,9,2) + '-' + substring (#HostPhysicalAddress,11,2)
SELECT #contexto=CAST(context_info AS varchar(128)) FROM master..sysprocesses WHERE spid=##SPID
IF (PatIndex( '%APPLICATION_USER=%',#contexto) is not null) and (PatIndex( '%APPLICATION_USER=%',#contexto) > 0)
set #ApplicationModifierUser=substring(ltrim(substring(#contexto,PatIndex( '%APPLICATION_USER=%',#contexto)+17,128)),1, charIndex( '///',ltrim(substring(#contexto,PatIndex( '%APPLICATION_USER=%',#contexto)+17,128) ) ) - 1 )
ELSE
set #ApplicationModifierUser=NULL
IF (PatIndex( '%OS_USER=%',#contexto) is not null) and ( PatIndex( '%OS_USER=%',#contexto)>0 )
set #SessionInfo_OSUser=substring(ltrim(substring(#contexto,PatIndex( '%OS_USER=%',#contexto)+8,128)),1, charIndex( '///',ltrim(substring(#contexto,PatIndex( '%OS_USER=%',#contexto)+8,128) ) ) - 1 )
ELSE
set #SessionInfo_OSUser=NULL
IF (PatIndex( '%LOGICAL_ADDRESS=%',#contexto) is not null) and (PatIndex( '%LOGICAL_ADDRESS=%',#contexto)>0)
set #HostLogicalAddress=substring(ltrim(substring(#contexto,PatIndex( '%LOGICAL_ADDRESS=%',#contexto)+16,128)),1, charIndex( '///',ltrim(substring(#contexto,PatIndex( '%LOGICAL_ADDRESS=%',#contexto)+16,128) ) ) - 1 )
ELSE
set #HostLogicalAddress=NULL
INSERT INTO AuditedOperations ( Application, Object, OperationType, ModifiedDate, ApplicationModifierUser, OSModifierUser, DBMSModifierUser, Host, HostLogicalAddress, HostPhysicalAddress, DBMSTransaction)
VALUES (APP_NAME(), 'HRPERSONS', 'U', GETDATE(), #ApplicationModifierUser, #OSUSER, #DBMSUSER, HOST_NAME(), #HostLogicalAddress, #HostPhysicalAddress, #DBMSTransaction)
Set #OperationNum = ##IDENTITY
INSERT INTO AuditedRows (OperationNum, RowPK)
SELECT #OperationNum, ISNULL(CAST(INSERTED.ID as nvarchar),CAST(DELETED.ID as nvarchar))
FROM INSERTED FULL OUTER JOIN DELETED ON INSERTED.ID=DELETED.ID
INSERT INTO AuditedRowsColumns (OperationNum, RowPK, ColumnName, ColumnAudReg, OldValue, NewValue)
SELECT #OperationNum, ISNULL(CAST(INSERTED.ID as nvarchar),CAST(DELETED.ID as nvarchar)), 'USERNAME','A', CONVERT( VARCHAR(3500),DELETED.USERNAME), CONVERT( VARCHAR(3500),INSERTED.USERNAME)
FROM INSERTED FULL OUTER JOIN DELETED ON INSERTED.ID=DELETED.ID
END
GO

Answer 1

Just add this:
INSERT INTO AuditedRows (OperationNum, RowPK)
SELECT #OperationNum, ISNULL(CAST(INSERTED.ID as nvarchar),CAST(DELETED.ID as nvarchar))
FROM INSERTED FULL OUTER JOIN DELETED ON INSERTED.ID=DELETED.ID
-- Restrict it to only those where the username is changing from or to %_ess
WHERE (deleted.username like '%_ess' or inserted.username like '%_ess')
INSERT INTO AuditedRowsColumns (OperationNum, RowPK, ColumnName, ColumnAudReg, OldValue, NewValue)
SELECT #OperationNum, ISNULL(CAST(INSERTED.ID as nvarchar),CAST(DELETED.ID as nvarchar)), 'USERNAME','A', CONVERT( VARCHAR(3500),DELETED.USERNAME), CONVERT( VARCHAR(3500),INSERTED.USERNAME)
FROM INSERTED FULL OUTER JOIN DELETED ON INSERTED.ID=DELETED.ID
-- Restrict it to only those where the username is changing from or to %_ess
WHERE (deleted.username like '%_ess' or inserted.username like '%_ess')