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What is ToDate(milliseconds) Function in Apache Pig ?
- The ToDate(milliseconds) function will generate a DateTime object which is done according to the given parameters which is given in the function.
- The ToDate(milliseconds) function uses scalars as parameters which is done in the ToDate(milliseconds)function
- ToDate(milliseconds) function converts the ISO or the customized string or the Unix timestamp to the DateTime object.
Syntax
grunt> ToDate(milliseconds)
grunt> ToDate(iosstring)
grunt> ToDate(userstring, format)
grunt> ToDate(userstring, format, timezone)
Example
- Ensure that we have a file named date.txt in the HDFS directory /pig_data/.
- This file contains the date-of-birth details of a particular person, id, date, and time.
wikitechy_date.txt
101,1995/07/25 09:00:00
102,1999/05/12 10:22:00
103,1997/10/17 03:11:44
- We have loaded the file into Pig with a relation name called date_data which is given below:
grunt> date_data = LOAD 'hdfs://localhost:9000/pig_data/wikitechy_date.txt' USING PigStorage(',')
as (id:int,date:chararray);
- Now you can calculate the DateTime object which is corresponding to the date-of-birth of the employee.
grunt> todate_data = foreach date_data generate ToDate(date,'yyyy/MM/dd HH:mm:ss')
as (date_time:DateTime >);
Verification
- We need to verify the content of this relation by using the Dump operator which is given below:
grunt> Dump todate_data;
Output
- The above statement stores the result in the relation named todate_data.
(1995-07-25T09:00:00.000+05:30)
(1999-05-12T10:22:00.000+05:30)
(1997-10-17T03:11:44.000+05:30)