The following SQL will list all of the idata_value’s for the DCI named 'SQL Cache Memory KB' for node 201
SELECT  TOP 1  items.item_id, items.node_id, idata_201.idata_timestamp, idata_201.idata_value
FROM        items INNER JOIN
                      idata_201 ON items.item_id = idata_201.item_id
WHERE    (items.description = 'SQL Cache Memory KB') AND (items.node_id = 201)
ORDER BY idata_201.idata_value DESC, idata_201.idata_timestamp ASC

The following SQL code will list the latest idata_value for the DCI named 'SQL Cache Memory KB' for node 201
select A.item_id,A.ts,D.idata_value,I.description from
(
      select item_id,max(idata_timestamp) as ts from idata_201 group by item_id
) A
join idata_201 AS D on A.item_id=D.item_id and D.idata_timestamp = A.ts
join items AS I on I.item_id = A.item_id
where description = 'SQL Cache Memory KB'

Server caches last values for each DCI, so when console displays them, data is coming directly from server's memory, not from SQL database.
However, you may use something like this:

If you wish to get last values for all DCIs on given node, you can use the following query:

select A.item_id,A.ts,D.idata_value,I.description from
(
	select item_id,max(idata_timestamp) as ts from netxms.idata_14 group by item_id
) A
join netxms.idata_14 AS D on A.item_id=D.item_id and D.idata_timestamp = A.ts
join netxms.items AS I on I.item_id = A.item_id

For node with id 14.

You can also define the stored procedure for retrieving last values for given node:

CREATE PROC LastValues
@Id integer
AS
EXEC ('
select A.item_id,A.ts,D.idata_value,I.description from
(
	select item_id,max(idata_timestamp) as ts from netxms.idata_' + @Id + ' group by item_id
) A
join netxms.idata_' + @Id + ' AS D on A.item_id=D.item_id and D.idata_timestamp = A.ts
join netxms.items AS I on I.item_id = A.item_id'
)
GO

I'm not good in SQL, so probably there are better way to do this

Best regards,
Victor

regards

Geoff

Short overview of database structure related to data collection:

All collected data stored in tables idata_xx, where xx is a node object id, so each node has it's own table for data. Structure of this table is quite simple:

You can get the list of nodes from nodes table, where you probably should be interested only in id and may be primary_ip fields.
Some fileds from "nodes" table:

Node's name, status, and comments can be obtained from "object_properties" table.
Some fileds from "object_properties" table:

Some information on database structure can also be obtained from this topic: https://www.netxms.org/forum/index.php/topic,198.0.html

Hope this helps!

Best regards,
Victor