SQL statement to find the time difference. such as the following data

MSISDN                    createtime                             closetime
138                  2011-5-17 15:30:00:000     2011-5-17 15:30:00:530
138                  2011-5-17 15:40:00:000     2011-5-17 15:40:00:530
How much time does it take to query the number 138 using the SQL statement?



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Select SUM (DateDiff (Millisecond,createtime, Closetime)) as total Hao seconds from table name where msisdn=138

Select SUM (DateDiff (Minute,createtime, Closetime)) as total number of seconds from table name where msisdn=138

Select SUM (DateDiff (Minute,createtime, Closetime)) as total minutes from table name where msisdn=138

Select SUM (DateDiff (Hour,createtime, Closetime)) as total hours from table name where msisdn=138

Select SUM (DateDiff (Day,createtime, Closetime)) as Total days from table name where msisdn=138

Select SUM (DateDiff (Week,createtime, Closetime)) as Total days from table name where msisdn=138

Select SUM (DateDiff (Month,createtime, Closetime)) as Total days from table name where msisdn=138

Select SUM (DateDiff (Quarter,createtime, Closetime)) as total number of seasons from table name where msisdn=138

Select SUM (DateDiff (Year,createtime, Closetime)) as total number of years from table name where msisdn=138

SQL statement to find the time difference. such as the following data