Two Queries
نویسندگان
چکیده
We consider the question whether two queries to SAT are as powerful as one query. We show that if PNP[1] = PNP[2] then Locally either NP = coNP or NP has polynomial-size circuits. PNP = PNP[1]. p2 p2=1. p2 = UPNP[1] \RPNP[1]. PH = BPPNP[1]. Moreover we extend work of Hemaspaandra, Hemaspaandra and Hempel to show that if P p2 [1] = P p2 [2] then p2 = p2 . We also give a relativized world where PNP[1] = PNP[2] but NP 6= coNP.
منابع مشابه
Improvement of the Analytical Queries Response Time in Real-Time Data Warehouse using Materialized Views Concatenation
A real-time data warehouse is a collection of recent and hierarchical data that is used for managers’ decision-making by creating online analytical queries. The volume of data collected from data sources and entered into the real-time data warehouse is constantly increasing. Moreover, as the volume of input data to the real time data warehouse increases, the interference between online loading ...
متن کاملبهبود الگوریتم انتخاب دید در پایگاه داده تحلیلی با استفاده از یافتن پرس وجوهای پرتکرار
A data warehouse is a source for storing historical data to support decision making. Usually analytic queries take much time. To solve response time problem it should be materialized some views to answer all queries in minimum response time. There are many solutions for view selection problems. The most appropriate solution for view selection is materializing frequent queries. Previously posed ...
متن کاملRelational Databases Query Optimization using Hybrid Evolutionary Algorithm
Optimizing the database queries is one of hard research problems. Exhaustive search techniques like dynamic programming is suitable for queries with a few relations, but by increasing the number of relations in query, much use of memory and processing is needed, and the use of these methods is not suitable, so we have to use random and evolutionary methods. The use of evolutionary methods, beca...
متن کاملارائه روشی پویا جهت پاسخ به پرس‌وجوهای پیوسته تجمّعی اقتضایی
Data Streams are infinite, fast, time-stamp data elements which are received explosively. Generally, these elements need to be processed in an online, real-time way. So, algorithms to process data streams and answer queries on these streams are mostly one-pass. The execution of such algorithms has some challenges such as memory limitation, scheduling, and accuracy of answers. They will be more ...
متن کاملCryptanalysis of some first round CAESAR candidates
ΑΕS _ CMCCv₁, ΑVΑLΑNCHEv₁, CLΟCv₁, and SILCv₁ are four candidates of the first round of CAESAR. CLΟCv₁ is presented in FSE 2014 and SILCv₁ is designed upon it with the aim of optimizing the hardware implementation cost. In this paper, structural weaknesses of these candidates are studied. We present distinguishing attacks against ΑES _ CMCCv₁ with the complexity of two queries and the success ...
متن کاملمدل جدیدی برای جستجوی عبارت بر اساس کمینه جابه‌جایی وزن‌دار
Finding high-quality web pages is one of the most important tasks of search engines. The relevance between the documents found and the query searched depends on the user observation and increases the complexity of ranking algorithms. The other issue is that users often explore just the first 10 to 20 results while millions of pages related to a query may exist. So search engines have to use sui...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- J. Comput. Syst. Sci.
دوره 59 شماره
صفحات -
تاریخ انتشار 1998