See the Java API documentation for the java.lang.Character class for
the exact level of Unicode Standard that is supported.
A collation is a set of rules for comparing characters in a character set.
In , the
collation rules affect comparisons of the CHAR and VARCHAR data types. Collation
rules also affect how the LIKE Boolean operator processes the CHAR, VARCHAR,
CLOB, and LONG VARCHAR data types.
The default
collation rule is based on the binary Unicode values of the characters. So a
character is greater than (>), equal to (=), or less than (<) another
character based on the numeric comparison of the Unicode values. This rule
allows for very efficient comparisons of character strings.
When LIKE comparisons are used,
compares one character
at a time for non-metacharacters. This is different from the way
processes =
comparisons. The comparisons with the = operator compare the entire character
string on the left side of the = operator with the entire character string on
the right side of the = operator. For details, see
.