I have a table in mysql which i s unique column ,but it want to allow the varchar column as case sensitive .

while insert
eg:Test123 and test123 report as duplicate value.

I need case sensitive but unique.

<property name="column1" column="COLUMN_STRING" unique="true" not-null="true" />

eg:
CREATE TABLE TEST(ID BIGINT AUTO_INCREMENT, COLUMN_STRING VARCHAR(128) CHARACTER SET utf8 COLLATE utf8_cs NOT NULL UNIQUE, PRIMARY KEY(ID));

How i can set the character set as case sensitive for particular column .

You can set a type on the property.

http://docs.jboss.org/hibernate/orm/3.3/reference/en/html/mapping.html#mapping-declaration-property

I'm not sure of the exact type you need, but you probably need to research into that. Or on possibly creating your own.