I am total newbie in SQL. I am having SQL Database in Azure (Azure Database). I am having "smart electrical switches" in my home. I managed to gather data about their usage in SQL table. Attached is example of the table. I would like to automatically calculate duration of time when particular light…

date calculations may be different between databases maybe something like this ? SELECT *, DATEDIFF(CURRENT_DATE(), timestamp) FROM table WHERE friendlyName = 'BalconyLight' ORDER BY timestamp DESC LIMIT 1 change table with your table name

UnborN, Thank you for your help, It is returning me an error. First I had to change some things... SELECT *, DATEDIFF(second, GETDATE(), timestamp) FROM dbo.switches WHERE friendlyName = 'BalconyLight' ORDER BY timestamp DESC LIMIT 1; But still getting an error. I don't think, I was clear enough…

i though sql syntax was standard for most databases .. apparently not :wink: SELECT TOP 1 *, DATEDIFF(second, GETDATE(), timestamp) as DateDiff FROM dbo.switches WHERE friendlyName = 'BalconyLight' AND event = 'off' ORDER BY timestamp DESC

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Calculating values in SQL instead of NodeRed

General

Steve-Mcl 25 January 2022 21:31 4

SQL server uses the syntax SELECT TOP 1 * FROM ...

not ... LIMIT 1

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Calculating values in SQL instead of NodeRed

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