We are converting our system from using Sybase's SQL Anywhere 10 to PostGres 8.3. In SQL Anywhere there technically isn't any difference in how a char and varchar is stored. They are all an array of char[1]. So we always just defined everything as a char since right truncation is the default.
In PostGres though if we are using a character type column to search should we define that as a varchar or a char or does it make any difference?