sql calculate difference balance between previous dates code example

Example 1: find difference in dates sql

SELECT DATEDIFF(day, date1,date2) AS DateDiff
/*
DATEDIFF accepts three arguments
1- day, month, year etc what form you need difference
2,3- dates 
*/

Example 2: SQL: calculate hours from two dates

DATEDIFF(second, start_date, end_date) / 3600.0