How to obtain partial time in SQL

Method for obtaining partial time in SQL: Sometimes, we may want to make some data statistics by month, by day, or by year. However, the actual data we save may be a very accurate occurrence time, which may be seconds. How to intercept a part of a time becomes a problem. There are two solutions: the most direct idea to use DatePart or Yea

Method for obtaining partial time in SQL: Sometimes, we may want to make some data statistics by month, by day, or by year. However, the actual data we save may be a very accurate occurrence time, which may be seconds. How to intercept a part of a time becomes a problem. There are two solutions: the most direct idea to use DatePart or Yea

Method for obtaining partial time in SQL:

Sometimes, we may want to make some data statistics on a monthly, daily, or yearly basis. However, the actual data we save may be a very accurate occurrence time, probably in seconds. How to intercept a part of a time becomes a problem.

There are two solutions:

The most direct idea is to use the DatePart or Year, Month, and Day functions.

CAST (

(

STR (YEAR (GETDATE () + '/' +

STR (MONTH (GETDATE () + '/' +

STR (DAY (GETDATE ()))

)

AS DATETIME

)

If you only need one year or one month, the previous one will be saved.

Method 2: Use time computing functions

For example, obtaining a month

DateAdd (month, DateDiff (month, 0, Coltime), 0)

The principle is that the database Time Value Coltime is reduced by 1900-1 to obtain the number of months in this period, and then the system adds-1-1 again.