Client Character Set

While working with strings, it is essential to keep the character set of the client connection in mind.If there is a mismatch between the character sets of the stored data and that of the client connection, the output results for string columns are automatically re-encoded, both when data are sent from the client to the server and when they are sent back from the server to the client.For example, if the database was created in the WIN1251 encoding but KOI8R or UTF8 is specified in the client’s connection parameters, the mismatch will be transparent.

The character set NONE is a special character set in Firebird.It can be characterized such that each byte is a part of a string, but the string is stored in the system without any clues about what constitutes any character: character encoding, collation, case, etc. are simply unknown.It is the responsibility of the client application to deal with the data and provide the means to interpret the string of bytes in some way that is meaningful to the application and the human user.

Data in OCTETS encoding are treated as bytes that may not be interpreted as characters.OCTETS provides a way to store binary data.The database engine has no concept of what it is meant to do with a string of bytes in OCTETS, other than store and retrieve it.Again, the client side is responsible for validating the data, presenting them in formats that are meaningful to the application and its users and handling any exceptions arising from decoding and encoding them.CHAR and VARCHAR with character set OCTETS have synonyms BINARY and VARBINARY.