How to create a datetime from parts in Oracle/T-SQL?
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I have a date (4/30/2012), an hour (4) and a minute (45). I need to convert that to an Oracle datetime value for comparison in a T-SQL/Oracle SELECT statement. Ideally, there would be a function like this (C# since I know it a little better):

    var date = "4/30/2012";
    var hour = "4";
    var minute = "45";
    DateTime myDateTime = convertDateTime(date, hour, minute);

I have a table with three columns to make up the date and time of an event. I have another table that has items that may or may not match based on their start and end dates. In pseudo SQL, here's what I'm trying to do:

    SELECT 
        G.Name, 
        (SELECT MAX(Cost) 
            FROM CrappyTable AS C 
            WHERE G.StartTime < convertDateTime(C.Date, C.Hour, C.Minute) 
            AND G.EndTime > convertDateTime(C.Date, C.Hour, C.Minute)) as Cost
    FROM GoodTable as G
    WHERE G.Price < 100.00;

> OR "Select name and max cost (from reported cost during a time range)
> where the price is less than $100."

Is there an existing function that might do something like the above `convertDateTime` function?

