近來版本文件增長有飛躍上的速度。搜索這類文件通常有時間範圍的限制。如何進行索引文件這些種類和回答time-travel phrase query在資料檢索的社群裡被廣泛討論。在本文中，我們提出了基於後綴樹索引文件新的框架來幫這些文件做索引。這個框架可以在保證空間複雜度O(nlogn + nlogT) bits和查詢的複雜度O(plogn + k）來存儲版本文件的索引，並支持任何pattern的查詢。在實作中，我們討論了一些實際問題，在此框架，並用簡潔的數據結構，減少我們的空間到接近為O(nlogT) bits。同時，我們也做了實驗來證明我們的概念。最後，我們還簡要提出了關於這個框架的延伸.

The volume of versioned documents is growing very quickly nowadays. How to exploit the redundancy among the documents to index the documents compactly, while supporting effi- cient time-constrained keyword queries has been a hot topic recently [Anand et al., SIGIR’11, SIGIR’12; He et al., CIKM’09, CIKM’10, SIGIR’11, SIGIR’12]. In this paper, we propose a new framework to index versioned documents, and extend the keyword queries into the more general phrase queries. Our index is based on suffix tree, taking O(n) space and answering a one-sided time-constrained phrase query for any phrase P in O((|P | + k) log n) time, where n is the dataset size and k is the output size. We discuss how to tune our framework with realistic assumptions; our experiments shows that under similar space budgets, our index supports queries five times faster than the baseline inverted lists when the query length |P| is at least four.

1 Introduction
1.1 Organization
2 Preliminaries
2.1 Generalized Suffix Tree
2.2 2-Dimensional Orthogonal Range Query
3 The Framework
3.1 Problem Definition
3.2 Index Method
3.3 QueryMethod
3.4 An Example Instantiation
4 Practical Optimization
4.1 Data Preprocessing
4.2 Framework Minimization
4.3 Query Enhancement
5 Experiment
5.1 Experimenting the Index Space
5.2 Experimenting the Query Performance
6 Further Discussion
7 Conclusion

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