## Spatial Joins Using R-trees: Breadth-First Traversal with Global Optimizations (1997)

Venue: | Proc. of VLDB |

Citations: | 88 - 4 self |

### BibTeX

@INPROCEEDINGS{Huang97spatialjoins,

author = {Yun-Wu Huang and Ning Jing and Elke A. Rundensteiner},

title = {Spatial Joins Using R-trees: Breadth-First Traversal with Global Optimizations},

booktitle = {Proc. of VLDB},

year = {1997},

pages = {396--405}

}

### Years of Citing Articles

### OpenURL

### Abstract

R-tree based spatial join is useful because of both its superior performance and the wide spread implementation of R-trees. We present a new R-tree join method called BFRJ (Breadth-First R-tree Join). BFRJ synchronously traverses both R-trees in breadthfirst order while processing join computation one level at a time. At each level, BFRJ creates an intermediate join index and deploys global optimization strategies (ordering, memory management, buffer management) to improve the join computation at the next level. We also present an experimental evaluation of the proposed optimizations as well as a performance comparison between BFRJ and the state-of-the-art approach. Our experimental results indicate that BFRJ with global optimizations can outperform the competitor by a significant margin (up to 50%). 0.05in This work was supported in part by the University of Michigan ITS Research Center of Excellence grant (DTFH61-93-X00017 -Sub) sponsored by the U.S. Dept. of Transportation and by...

### Citations

2221 | R-trees : A Dynamic Index Structure for Spatial Searching
- Guttman
- 1984
(Show Context)
Citation Context ... allow for spatial database engines to trade off between using these versus other join techniques for processing spatial queries. 3 Background on R-Tree Spatial Joins 3.1 The R-tree Structure R-trees =-=[7]-=- are an extension of B-trees [1] that store multi-dimensional data. A non-leaf node in an R-tree contains entries of the form ! addr; mbr ? where addr is the address of a child node and mbr is the MBR... |

981 | The r*-tree: an efficient and robust access method for points and rectangles - Beckmann, Kriegel, et al. - 1990 |

488 |
The R -tree: an efficient and robust access method for points and rectangles
- Beckmann, Kriegel, et al.
- 1990
(Show Context)
Citation Context ... of the form ! oid; mbr ? where oid refers to a spatial object stored in the database and mbr is the MBR of that spatial object. In most R-tree variants, entry MBRs are allowed to overlap one another =-=[2, 7, 5]-=-. This means that there may be more than one search path. Recently proposed R-tree variants tried to minimize the overlap between the entry MBRs. Among them, R*-tree [2] introduces heuristics that yie... |

382 | The grid file: an adaptable, symmetric multikey file structure
- Nievergelt, Hinterberger, et al.
- 1984
(Show Context)
Citation Context ...into the 1-dimensional domain. Spatial join is then conducted on the B + -tree structures that store z-ordering values of the spatial data. In [16], spatial join indexes are computed using Grid files =-=[13]-=- to index the spatial data. In [6], a model of the generalization tree is proposed to compare the tree-based spatial joins with the alternative approaches. Spatial joins based on depth-first traversal... |

323 | E cient Processing of Spatial Joins using R-trees
- Brinkhoff, Kriegel, et al.
- 1993
(Show Context)
Citation Context ...oin queries is an extremely I/O and CPU expensive process. This paper presents a new method for spatial joins with a significant performance improvement (up to 50%) over the state-of-the-art approach =-=[3]-=-. Like other spatial join techniques [3], our method is based on existing R-tree indexes for the two input data sets. Using R-trees for spatial join processing is effective because R-tree (and its var... |

297 | The r+ tree: a dynamic index for multi-dimensional objects - Sellis, Roussopoulos, et al. - 1987 |

254 |
Organization and maintenance of large ordered indexes
- Bayer, McCreight
- 1972
(Show Context)
Citation Context ...nes to trade off between using these versus other join techniques for processing spatial queries. 3 Background on R-Tree Spatial Joins 3.1 The R-tree Structure R-trees [7] are an extension of B-trees =-=[1]-=- that store multi-dimensional data. A non-leaf node in an R-tree contains entries of the form ! addr; mbr ? where addr is the address of a child node and mbr is the MBR that encloses MBRs of all entri... |

219 | On Packing R-Trees
- Kamel, Faloutsos
- 1993
(Show Context)
Citation Context ... of the form ! oid; mbr ? where oid refers to a spatial object stored in the database and mbr is the MBR of that spatial object. In most R-tree variants, entry MBRs are allowed to overlap one another =-=[2, 7, 5]-=-. This means that there may be more than one search path. Recently proposed R-tree variants tried to minimize the overlap between the entry MBRs. Among them, R*-tree [2] introduces heuristics that yie... |

168 |
Spatial query processing in an object-oriented database system
- Orenstein
- 1986
(Show Context)
Citation Context ...k of BFRJ, followed by Section 5 where BFRJ global optimizations are proposed. We present our experimental results in Section 6 and conclude the paper in Section 7. 2 Related Work on Spatial Joins In =-=[14]-=-, the z-ordering technique is used to transform multi-dimensional data into the 1-dimensional domain. Spatial join is then conducted on the B + -tree structures that store z-ordering values of the spa... |

166 | Partition based spatial-merge join
- Patel, DeWitt
- 1996
(Show Context)
Citation Context ... GIS databases, Postgres, and MapInfo all offer R-tree support. Furthermore, join processing based on Rtrees has been shown to result in superior performance as compared to alternate index structures =-=[15]-=-. While the state-of-the-art R-tree join approach [3] follows a depth-first order for traversing the two input R-trees, we demonstrate in this paper that a spatial join technique based on the breadth-... |

95 | Spatial hash-joins
- Lo, Ravishankar
- 1996
(Show Context)
Citation Context ...ree indexes exist for both spatial data sets. Its performance even has become the yardstick used by other researchers to measure the performance of their proposed non-index based spatial join methods =-=[12, 15]-=-. Besides R-tree joins, recent spatial join research has also focused on joining spatial data when the associated spatial indexes do not exist for the data sets. When no index exists for the two input... |

92 | E cient Computation of Spatial Joins
- Gunther
- 1993
(Show Context)
Citation Context ...ial join is then conducted on the B + -tree structures that store z-ordering values of the spatial data. In [16], spatial join indexes are computed using Grid files [13] to index the spatial data. In =-=[6]-=-, a model of the generalization tree is proposed to compare the tree-based spatial joins with the alternative approaches. Spatial joins based on depth-first traversal of R-trees were proposed in [3]. ... |

74 |
Spatial Join indices
- Rotem
- 1991
(Show Context)
Citation Context ...ng technique is used to transform multi-dimensional data into the 1-dimensional domain. Spatial join is then conducted on the B + -tree structures that store z-ordering values of the spatial data. In =-=[16]-=-, spatial join indexes are computed using Grid files [13] to index the spatial data. In [6], a model of the generalization tree is proposed to compare the tree-based spatial joins with the alternative... |

33 | A cost model for estimating the performance of spatial joins using r-trees
- HUANG, JING, et al.
- 1997
(Show Context)
Citation Context ...ee join processing task making it practical for even very large spatial data sets as commonly found in advanced GIS applications. Finally, newly developed estimation techniques for spatial join costs =-=[11]-=- will allow for spatial database engines to trade off between using these versus other join techniques for processing spatial queries. 3 Background on R-Tree Spatial Joins 3.1 The R-tree Structure R-t... |

32 | ªOrganization and Maintenance of Large Ordered - Bayer, McCreight - 1970 |

9 | Integrated Query Processing Strategies for Spatial Path Queries
- Huang, Jing, et al.
- 1997
(Show Context)
Citation Context ... A successful spatial database management system must provide efficient query functions such as spatial joins that combine multiple data sets based on a spatial predicate (e.g., intersect or contain) =-=[9]. Examples of spatia-=-l join queries are Q1: "Find all parks which are in a city." and Q2: "Find all trails that go through some forest." In Q1, the two data sets are parks and cities, the spatial predi... |

9 | of Census., “Tiger/Lines Precensus Files - Bureau - 1990 |

5 |
Improving Spatial Intersect Joins Using Symbolic Intersect Detection
- Huang, Jones, et al.
- 1997
(Show Context)
Citation Context ... recent work on R-tree based joins, the BFRJ technique we propose in this paper optimizes the filter step of spatial join processing (i.e., it works at the Minimum Bounding Rectangle (MBR) level). In =-=[10]-=-, on the other hand, we present an optimization of the refinement step of spatial join processing, called SID (Symbolic Intersect Detection), for which we demonstrate unparalleled performance improvem... |

2 |
of Census., "Tiger/Lines Precensus Files
- Bureau
- 1990
(Show Context)
Citation Context ...f streets (131,461 objects) and a data set of rivers and railway tracts (128,971 objects) from an area in California. The data is derived from the TIGER/Line files distributed by the US Census Bureau =-=[4]-=-. We created two Hilbert curve packed R-trees [5], each for a data set, with the page size set to 4 KBytes. 6.1 Experiments on Intermediate Join Index Ordering Optimizations We implemented IJI orderin... |

1 | BFRJ: Global Optimization of Spatial Joins Using R-trees
- Huang, Jing, et al.
- 1997
(Show Context)
Citation Context ...t the heights of the two input R-trees are the same (hR = hS), however a generalization for this BFRJ algorithm for trees of unequal height is straightforward and can be found in our technical report =-=[8]-=-. PROCEDURE BFRJ (R, S) // R, S are two R-trees, hR = hS // IJI[i] intermediate join index at level i DATA STRUCTURES: set IJI[hR] := ;; 01 IJI[0] := Node P air Join(nR 0 ; nS 0 ); 02 // join two root... |

1 |
Performance Specifications for Barracuda 2LP Family Disk Drives
- Corporation
- 1996
(Show Context)
Citation Context ..., and transfer time. The 10 ms page access time that we use here is derived from the performance specifications of one class of modern disk drives, namely the Seagate Barracuda 2LP family disk drives =-=[17]-=- 6 . The results in Figure 9 show that Combo1 has a better overall performance than DFRJ and Combo2 when the buffer sizes are small. When a larger buffer is available, the results in Figure 10 indicat... |

1 | Partition Based Spatial-Merge Join - Pate, M, et al. - 1996 |

1 | Corporation, “Performance Specifications for Barracuda 2LP Family Disk Drives,” http://www:seagate.com - Seagate - 1996 |