Optimal-Location-Selection Query Processing in Spatial Databases

Abstract—This paper introduces and solves a novel type of spatial queries, namely, Optimal-Location-Selection (OLS) search, which has many applications in real life. Given a data object set DA, a target object set DB, a spatial region R, and a critical distance dc in a multidimensional space, an OLS query retrieves those target objects in DB that are outside R but have maximal optimality. Here, the optimality of a target object b 2 DB located outside R is defined as the number of the data objects from DA that are inside R and meanwhile have their distances to b not exceeding dc. When there is a tie, the accumulated distance from the data objects to b serves as the tie breaker, and the one with smaller distance has the better optimality. In this paper, we present the optimality metric, formalize the OLS query, and propose several algorithms for processing OLS queries efficiently. A comprehensive experimental evaluation has been conducted using both real and synthetic data sets to demonstrate the efficiency and effectiveness of the proposed algorithms. Index Terms—Query processing, optimal-location-selection, spatial database, algorithm. Ç

Development of a specific domain language (DSL) graphic for the modeling of spatial databases

El modelado de bases de datos espaciales se desarrolla actualmente requiriendo que los usuarios tengan conocimiento en algunas herramientas y lenguajes de propósito general lo que en ocasiones dificulta el proceso de diseño e implementación de estas en entornos computacionales pues se requiere de un gran aprendizaje y conocimiento de esos lenguajes y de procedimientos complejos y engorrosos. Los lenguajes de dominio específico ofrecen una alternativa para facilitar muchos de estos procesos, por ello se evidencia necesario desarrollar una propuesta de metamodelo y su respectivo DSL gráfico que facilite el modelamiento de este tipo de bases de datos espaciales relacionales para los usuarios finales. Para ello se partirá de una propuesta abstracta para luego llevarla a una sintaxis concreta y posteriormente poder transformar los modelos en código para las extensiones Open Source como PostGIS y MySQL Spatial con el fin que los usuarios finales puedan emplear la propuesta de DSL gráfico y experimentar mejoras en el proceso de modelado de su bases de datos.The modeling of Spatial Databases is currently being developed, requiring users to have knowledge in some general purpose tools and languages, which sometimes hinders the process of designing and implementing these in computer environments because it requires a great learning and knowledge of those languages ​​and complex and cumbersome procedures. Specific Domain Languages ​​offer an alternative to facilitate many of these processes, therefore it is necessary to develop a metamodel proposal and its respective DSL graph that facilitates the modeling of this type of Relational Spatial Databases for end users. This will be based on an abstract proposal and then take it to a specific syntax and then transform the models into code for Open Source extensions such as PostGIS and MySQL Spatial so that end users can use the DSL graphic proposal and experience improvements in the process of modeling your Databases