public SQLInsertClause insertOnDuplicateKeyUpdate(RelationalPath<?> entity, String clause) {
        SQLInsertClause insert = insert(entity);
        insert.addFlag(Position.END, " on duplicate key update " + clause);
        return insert;
    }
Create a INSERT ... ON DUPLICATE KEY UPDATE clause

@param entity table to insert to
@param clause clause
@return insert clause
querydsl-sql/src/main/java/com/querydsl/sql/mysql/MySQLQueryFactory.java