ASA Database Administration Guide
International Languages and Character Sets
Understanding character sets in software
The database collation sequence includes the notion of alphabetic ordering of letters, and extends it to include all characters in the character set, including digits and space characters.
More than one character can be associated with each sort position. This is useful if you wish, for example, to treat an accented character the same as the character without an accent.
Two characters with the same sort position are considered identical in all ways by the database. Therefore, if a collation assigned the characters a and e to the same sort position, then a query with the following search condition:
WHERE col1 = 'want'
is satisfied by a row for which col1 contains the entry went.
At each sort position, lowercase and uppercase forms of a character can be indicated. For case sensitive databases, the lowercase and uppercase characters are not treated as equivalent. For case insensitive databases, the lowercase and uppercase versions of the character are considered equivalent.
TipAny code that selects a default collation for a German system should select 1252LATIN1, not 1252DEU. 1252DEU differentiates between characters with and without an umlaut, while 1252LATIN1 does not. 1252LATIN1 considers Muller and Müller equal, but 1252DEU does not consider them equal. Because 1252DEU views characters with umlauts as separate characters, it has the following alphabetic ordering: ob, öa. |
First-byte collation orderings for multibyte character sets