On Sun, Dec 10, 2017 at 11:09 PM, Tsunakawa, Takayuki <tsunakawa.takay@xxxxxxxxxxxxxx> wrote: > It is embarrassing to ask such a thing, but is there any way to sort character column values in EBCDIC order inside the PostgreSQL server? i.e. is it possible to use EBCDIC collation in PostgreSQL, say, by using ICU or something? We need to run on a certain mainframe. There is no need for embarrassment. I think that you mean that you'd like to get behavior equivalent to the "C" locale with an EBCDIC encoding. Right? I think that you could use ICU to do this with some work. ICU collations are not tied to a particular encoding, unlike the libc collations (they support most but not all collations). That said, the idea of an "EBCDIC collation" seems limiting. Why should a system like DB2 for the mainframe (that happens to use EBCDIC as its encoding) not have a more natural, human-orientated collation even while using EBCDIC? ISTM that the point of using the "C" locale (with EBDIC or with UTF-8 or with any other encoding) is to get a performance benefit where the actual collation's behavior doesn't matter much to users. Are you sure it's really important to be *exactly* compatible with EBCDIC order? As long as you're paying for a custom collation, why not just use a collation that is helpful to humans? -- Peter Geoghegan