mssql-doc updated with the list of tables which should have permission (

#30137)

metricbeat/docs/modules/mssql.asciidoc

@@ -15,6 +15,21 @@ This is the https://www.microsoft.com/en-us/sql-server/sql-server-2017[Microsoft
 
 The module is being tested with https://hub.docker.com/r/microsoft/mssql-server-linux/[2017 GA] version under Linux
 
+[float]
+=== Permission/Access required for tables
+
+1.`transaction_log` :
+
+* sys.databases
+* sys.dm_db_log_space_usage
+* sys.dm_db_log_stats(DB_ID)
+
+2.`performance` :
+
+* sys.dm_os_performance_counters
+
+If you browse MSDN for above tables, you will find "Permissions" section which defines the permission needed, e.g https://docs.microsoft.com/en-us/sql/relational-databases/system-dynamic-management-views/sys-dm-db-log-space-usage-transact-sql?view=sql-server-ver15[Permissions]
+
 [float]
 === Metricsets
 

x-pack/metricbeat/module/mssql/_meta/docs.asciidoc

@@ -5,6 +5,21 @@ This is the https://www.microsoft.com/en-us/sql-server/sql-server-2017[Microsoft
 
 The module is being tested with https://hub.docker.com/r/microsoft/mssql-server-linux/[2017 GA] version under Linux
 
+[float]
+=== Permission/Access required for tables
+
+1.`transaction_log` :
+
+* sys.databases
+* sys.dm_db_log_space_usage
+* sys.dm_db_log_stats(DB_ID)
+
+2.`performance` :
+
+* sys.dm_os_performance_counters
+
+If you browse MSDN for above tables, you will find "Permissions" section which defines the permission needed, e.g https://docs.microsoft.com/en-us/sql/relational-databases/system-dynamic-management-views/sys-dm-db-log-space-usage-transact-sql?view=sql-server-ver15[Permissions]
+
 [float]
 === Metricsets