Tuesday, August 20, 2013

Collation

Collation


Collation refers to a set of rules that determine how data is sorted and compared. Character data is sorted using rules that define the correct character sequence, with options for specifying case-sensitivity, accent marks, kana character types and character width.

Types of collation are:

1.   Case sensitivity

2.   Accent sensitivity

3.   Kana Sensitivity

4.   Width sensitivity


 Case sensitivity

If A and a, B and b, etc. are treated in the same way then it is case-insensitive. A computer treats A and a differently because it uses ASCII code to differentiate the input. The ASCII value of A is 65, while a is 97. The ASCII value of B is66 and b is 98.

 Accent sensitivity

If a and á, o and ó are treated in the same way, then it is accent-insensitive. A computer treats a and á differently because it uses ASCII code for differentiating the input. The ASCII value of a is 97 and áis 225. The ASCII value of o is111 and ó is 243.

 Kana Sensitivity

When Japanese kana characters Hiragana and Katakana are treated differently, it is called Kana sensitive.

 Width sensitivity

When a single-byte character (half-width) and the same character when represented as a double-byte character (full-width) are treated differently then it is width sensitive.