sp_readerrorlog (Transact-SQL)
Applies to: 
SQL Server
Allows you to read the contents of the SQL Server or SQL Server Agent error log file and filter on keywords.
Transact-SQL syntax conventions
Syntax
sp_readerrorlog
[ [ @p1 = ] p1 ]
[ , [ @p2 = ] p2 ]
[ , [ @p3 = ] N'p3' ]
[ , [ @p4 = ] N'p4' ]
[ ; ]
Arguments
[ @p1 = ] p1
The integer value of the log you want to view. @p1 is int, with a default of 0. The current error log has a value of 0. The previous is 1 (ERRORLOG.1), the one before previous is 2 (ERRORLOG.2), and so on.
[ @p2 = ] p2
The integer value for the product whose log you want to view. @p2 is int, with a default of NULL. Use 1 for SQL Server or 2 SQL Server Agent. If a value isn't specified, the SQL Server product is used.
[ @p3 = ] N'p3'
The string value for a string you want to filter on when viewing the error log. @p3 is nvarchar(4000), with a default of NULL.
[ @p4 = ] N'p4'
The string value for an additional string you want to filter on to further refine the search when viewing the error log. @p4 is nvarchar(4000), with a default of NULL. This parameter provides an extra filter to the first string search @p3.
Return code values
None.
Result set
Displays the content of the requested error log. If filter strings are used, only the lines that match those strings are displayed.
Remarks
Every time SQL Server is started, the current error log is renamed to ERRORLOG.1; ERRORLOG.1 becomes ERRORLOG.2, ERRORLOG.2 becomes ERRORLOG.3, and so on. sp_readerrorlog enables you to read any of these error log files as long as the files exist.
Permissions
Execute permissions for sp_readerrorlog are restricted to members of the sysadmin fixed server role.
Examples
The following example cycles the SQL Server error log.
A. Read the current SQL Server error log
EXEC sp_readerrorlog;
B. Show the previous SQL Server Agent error log
EXEC sp_readerrorlog 1, 2;
C. Find log messages that indicate a database is starting up
EXEC sp_readerrorlog 0, 1, 'database', 'start';