I store some time values in sqlite in %H:%M string format (for example "15:43"), but I would like to get them out formatted in 12 hour format with AM/PM indicators (for example "3:43 PM"). Is this possible with sqlite (and if so, how), or do I need to do this in my application code?
Unless you extend sqlite with your own custom function, you'll have to do this is code.
sqlite's strftime date formatting function only supports a small subset of its C counterpart, insufficient for your problem. sqlite also lacks a selection construct like IF or CASE, making simple if/else impossible.