Convert timestamp to date in Oracle SQL

Question

How can we convert timestamp to date?

The table has a field, start_ts which is of the timestamp format:

\'05/13/2016 4:58:1         


        

Answer 1

If the datatype is timestamp then the visible format is irrelevant.

You should avoid converting the data to date or use of to_char. Instead compare the timestamp data to timestamp values using TO_TIMESTAMP()

WHERE start_ts >= TO_TIMESTAMP('2016-05-13', 'YYYY-MM-DD')
   AND start_ts < TO_TIMESTAMP('2016-05-14', 'YYYY-MM-DD')

Answer 2

You can use:

select to_date(to_char(date_field,'dd/mm/yyyy')) from table

Answer 3

This may not be the correct way to do it. But I have solved the problem using substring function.

Select max(start_ts), min(start_ts)from db where SUBSTR(start_ts, 0,9) ='13-may-2016'

using this I was able to retrieve the max and min timestamp.

Answer 4

CAST(timestamp_expression AS DATE)

For example, The query is : SELECT CAST(SYSTIMESTAMP AS DATE) FROM dual;

Answer 5

Format like this while selecting:

to_char(systimestamp, 'DD-MON-YYYY')

Eg:

select to_char(systimestamp, 'DD-MON-YYYY') from dual;

Answer 6

Try using TRUNC and TO_DATE instead

WHERE
    TRUNC(start_ts) = TO_DATE('2016-05-13', 'YYYY-MM-DD')

Alternatively, you can use >= and < instead to avoid use of function in the start_ts column:

WHERE
   start_ts >= TO_DATE('2016-05-13', 'YYYY-MM-DD')
   AND start_ts < TO_DATE('2016-05-14', 'YYYY-MM-DD')