Question: How to I compare dates in
Oracle?
Answer: In Oracle, dates have a DATE
internal format and comparing DATES should be with matching data
types, preferably a DATE to DATE datatype. If you avoid this
data type mismatch and convert your text with the to_date
function it is easy to compare dates in Oracle;
where my_date_col > to_date(2010-10-12,YYYY-MM-DD);
Below we compare to DATE in character format:
where to_char(my_char_col) > 2015-10-12
Comparing dates the wrong way
These Oracle date comparisons works, but no index cannot be used
because date2 is invalidated with the trunc function (unless you
create a function-based index on trunc(date2,'YYYY:MM').
where to_char(DATE1,'YYYY:MM')
>= to_char(DATE2,'YYYY:MM')
where trunc(date1,'mm') >=
trunc(date2,'mm');
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