对于SQL Server中使用游标的每个循环

Question

I have a table with 4 cols. HouseNo, Date, Time and Temp.

I have managed to obtain the different HouseNos in a separate table. Now i want to insert all the dates for all the house nos.

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Sample Data from table. There are like a few million rows like this.

HouseNo Date Time Temp
102 1/1/2010 10:00 67
102 2/1/2010 10:00 73
102 3/1/2010 10:00 75
103 1/1/2010 10:00 69
103 2/1/2010 10:00 63
104 1/1/2010 10:00 71
104 2/1/2010 10:00 12

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Expected Output is

table 1

102 1/1/2010 
102 2/1/2010 
102 3/1/2010

table 2

103 1/1/2010 
103 2/1/2010

table 3

104 1/1/2010 
104 2/1/2010

Then i want to be able to loop through each row in the tables derieved to perform some operation on the temperature field.

Answer 1

If you have one ON/OFF pair per day and the OFF is always before the ON, this gets you the duration.

SELECT 
HouseNo,  
Date, 
DATEDIFF(s,
   MIN(CASE WHEN Relay='OFF' THEN Time ELSE NULL END),
   MIN(CASE WHEN Relay='ON' THEN Time ELSE NULL END)
) As OffDuration
FROM YourTable
GROUP BY HouseNo,  Date

But any normal real life dataset will have multiple ON/OFF pairs. Can you give more detail?

Answer 2

something like this ?

    CREATE TABLE new_table
    AS (SELECT * FROM old_table);

you can also put some WHERE part and SELECT