Collations have these general characteristics:
Two different character sets cannot have the same collation.
Each character set has one collation that is the default collation. For example,the default collation for latin1 is latin1_swedish_ci. The output for SHOW CHARACTER SET indicates which collation is the default for each displayed character set.
There is a convention for collation names: They start with the name of the character set with which they are associated,they usually include a language name,and they end with _ci (case insensitive),_cs (case sensitive),or _bin (binary).
In cases where a character set has multiple collations,it might not be clear which collation is most suitable for a given application. To avoid choosing the wrong collation,it can be helpful to perform some comparisons with representative data values to make sure that a given collation sorts values the way you expect.
