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sql - Select from table by knowing only date without time (ORACLE)

I'm trying to retrieve records from table by knowing the date in column contains date and time.

Suppose I have table called t1 which contains only two column name and date respectively.

The data stored in column date like this 8/3/2010 12:34:20 PM.

I want to retrieve this record by this query for example (note I don't put the time):

Select * From t1 Where date="8/3/2010"

This query give me nothing !

How can I retrieve date by knowing only date without the time?

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DATE is a reserved keyword in Oracle, so I'm using column-name your_date instead.

If you have an index on your_date, I would use

WHERE your_date >= TO_DATE('2010-08-03', 'YYYY-MM-DD')
  AND your_date <  TO_DATE('2010-08-04', 'YYYY-MM-DD')

or BETWEEN:

WHERE your_date BETWEEN TO_DATE('2010-08-03', 'YYYY-MM-DD')
                    AND TO_DATE('2010-08-03 23:59:59', 'YYYY-MM-DD HH24:MI:SS')

If there is no index or if there are not too many records

WHERE TRUNC(your_date) = TO_DATE('2010-08-03', 'YYYY-MM-DD')

should be sufficient. TRUNC without parameter removes hours, minutes and seconds from a DATE.


If performance really matters, consider putting a Function Based Index on that column:

CREATE INDEX trunc_date_idx ON t1(TRUNC(your_date));

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