citect & MS SQL database

[valerio81 0]

Hi all, i'm using for a new project, a connection to a SQL database. I used in the past the connection to Access DB adding each minute a new line with lot of Citect Tags to do some reports. Now, in this project, i need to read every second (or 5 seconds maybe) last row and save the 3 parameters of the last row in 3 variables on CitectSCADA. the exaple could be like this ID Name Code Value 1 N_1 C_1 V_1 2 N_2 C_2 V_2 3 N_3 C_3 V_3 4 N_4 C_4 V_4 the customer add a row everytime he changes Name, Code and Value (example a new order) and i should read last information until the customer changes it again, adding another new line Have you any advice? I dont know very well how to use MS SQL query. Thank you Valerio

[Chris Elston 79]

I think something like this QUERY would work. SELECT * from table_name WHERE ID=IDENT_CURRENT('table_name')

[valerio81 0]

thank you very much. i test it next week and I let you know!

[valerio81 0]

thanks Chris, it works good! I have another question, i think last one:-) How can I read, for example last 4 rows? You think is ok to read ID column and keep higher value as last one and then make a query reading values from MAXID-4 to MAXID ? Or there is a simpler query? It's very funny to learn this new language:-D Thanks

[Chris Elston 79]

Depends on which SQL database you have. This one: SELECT TOP 4 FROM Table_Name; Or this one: SELECT * FROM Table_Name LIMIT 0 4; Might do the trick.