I am trying to create a program using the postgresql database with lazarus.
I got the following error in compiling:
registersqldb.pas(72,3) Fatal: Can not find unit mysql55conn used by registersqldb.
what is wrong?
The project was probably created with a development version of FPC. (2.7.1 or 2.6.1), and you are probably trying to compile it with a stock release (2.6.0) version.
Solution: install a 2.6.1 based lazarus snapshot, or change the program to use an older mysql library.
I would recommend against 2.7.1 based snapshots. Too much is broken atm.
Disclaimer: I don't use mysql, so don't know exact compatibility details between versions, except that it is not always easy.