Different languages have different sort orders. In addition, different cultures or countries that use the same alphabets may sort words differently.
For example, in Danish, Æ is after Z, while Y and Ü are considered to be variants of the same letter.
Sort order can:
Another common sorting issue is combining letters into a single character. For example, in traditional Spanish, ch is a distinct character that comes after c, which means that the correct order is: cerveza, colorado, cheremoya. This means that the letter c cannot be sorted until Oracle has checked whether the next letter is an h.
Oracle provides the following types of sorts:
One way to sort character data is based on the numeric values of the characters defined by the character encoding scheme.
This is called a binary sort. Binary sorts are the fastest type of sort. They produce reasonable results for the English alphabet because the ASCII and EBCDIC standards define the letters A to Z in ascending numeric value.
Note:
When characters used in other languages are present, a binary sort usually does not produce reasonable results. For example, an ascending ORDER BY query returns the character strings ABC, ABZ, BCD, ÄBC, when Ä has a higher numeric value than B in the character encoding scheme. A binary sort is not usually linguistically meaningful for Asian languages that use ideographic characters.