How to combine date from one column and time from another

Question

Currently I'm trying to select a datetime column from two date columns. I'm having the following situation:

1. FROMDATE column which contains dates without time, e.g. 08-01-2017 00:00:00
2. FROMTIME column which contains times without a date, e.g. 01-01-1899 13:50:00

Now I want to select both within one column, e.g. SELECT (<what ever>) as FROMDATETIME ...

Expected result: 08-01-2017 13:50:00

But I'm not able to extract the date and time parts and add them together as a datetime.

Spoken in a kind of meta sql: select (date(FROMDATE) + time(FROMTIME)) as FROMDATETIME.

I've tried a lot with TO_CHAR and TO_DATE but was not able to get the expecting result.

Answer 1

Here you go:

SELECT TO_DATE(TO_CHAR(t.fromdate,'dd-mm-yyyy') ||
               ' ' ||
               TO_CHAR(t.fromtime,'hh24:mi:ss'),'dd-mm-yyyy hh24:mi:ss') as full_date_col 
FROM YourTable t