Suppose you have a numeric column of dates in YYYYMMDD format. In this format, the value 20150101 represents January 1, 2015. You want to convert the numeric column to a date/time column in MM/DD/YYYY format. There are two ways to do this: use Change Data Type and Format Column, or use the Calculator.
In the following examples, C1 has a numeric data type and contains dates in this format: YYYYMMDD. C2 is empty.
Use Change Data Type to change the data type of the column to text. Then use Format Column to change the data type to date/time and specify the date/time format.
Using the Calculator, you can convert the data in one step. The result is stored in C2.