weekday

Description

The weekday function is used to calculate and return the day of the week for a given date (date type) or timestamp (timestamp type). This function is very useful for scenarios that require data processing or statistics based on the day of the week.

Parameter Description

• expr: date or timestamp_ltz type, representing the date or timestamp for which the day of the week needs to be calculated.

Return Result

Returns an integer representing the day of the week. Where 0 represents Monday, 1 represents Tuesday, and so on, with 6 representing Sunday.

Usage Example

1. Calculate the day of the week for the current time:

   SELECT weekday(current_timestamp()) as res;
   

The result will return the day of the week when the query is executed.

2. Calculate the day of the week for a specific date:

   SELECT weekday('2022-03-31') as res;
   +-----+
   | res |
   +-----+
   | 3   |
   +-----+
   

3. Calculate which day of the week the timestamp belongs to:

   SELECT weekday(timestamp_ltz '2022-03-31 13:15:00')as res;
   +-----+
   | res |
   +-----+
   | 3   |
   +-----+
   

Notes

• When the input date or timestamp is invalid, the weekday function will return an error.
• This function may have differences in the calculation of weekdays for different regions, please adjust according to the actual situation.

Conclusion

The weekday function is a simple and practical tool that can help users quickly get the day of the week for a given date or timestamp. Through the above examples, users can better understand and use this function.