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declarations in the Prolog: Schema Imports A namespace is defined by a schema This statement binds a prefix to a namespace and imports the schema that defines the namespace: import schema namespace acme ... /names" All definitions in the schema become visible (used for validation) The system is responsible for finding the schema You can provide a "hint" about the schema location: import schema namespace acme ...doi:10.1145/872757.872877 dblp:conf/sigmod/Chamberlin03 fatcat:kyh47uvewfeftc27k56xqvdoqq
SIGMOD'15, May 31-June 4, 2015, Melbourne, Victoria, Australia. ACM 978-1-4503-2758-9/15/05. http://dx.doi.org/10.1145/2723372.2746480. : Volatile-Page is just made. No Snapshot yet. ...doi:10.1145/2723372.2746480 dblp:conf/sigmod/Kimura15 fatcat:swfgjpkvendwla3yncycqwdtl4
Figure 1 : 1 SIGMOD/PODS'14, Jun 22-27 2014, Snowbird, UT, USA ACM 978-1-4503-2376-5/14/06. http://dx.doi.org/10.1145/2588555.2612665. ...doi:10.1145/2588555.2612665 dblp:conf/sigmod/Xie14 fatcat:67sjtd22p5esrik5a3s7hx4wuy
Purpose -The paper aims to raise awareness in the industry of design automation tools, especially in early design phases, by demonstrating along a case study the seamless integration of a prototypically implemented optimization, supporting design space exploration in the early design phase and an in operational use product configurator, supporting the drafting and detailing of the solution predominantly in the later design phase. Design/methodology/approach -Based on the comparison of modeleddoi:10.1145/223784.223882 dblp:conf/sigmod/Sheth95 fatcat:p7iahyb6nnetjbz4syzo2h3ptu
more »... arison of modeled as-is and to-be processes of ascent assembly designs with and without design automation tools, an automation roadmap is developed. Using qualitative and quantitative assessments, the potentials and benefits, as well as acceptance and usage aspects, are evaluated. Findings -Engineers tend to consider design automation for routine tasks. Yet, prototypical implementations support the communication and identification of the potential for the early stages of the design process to explore solution spaces. In this context, choosing from and interactively working with automatically generated alternative solutions emerged as a particular focus. Translators, enabling automatic downstream propagation of changes and thus ensuring consistency as to change management were also evaluated to be of major value. Research limitations/implications -A systematic validation of design automation in design practice is presented. For generalization, more case studies are needed. Further, the derivation of appropriate metrics needs to be investigated to normalize validation of design automation in future research. Practical implications -Integration of design automation in early design phases has great potential for reducing costs in the market launch. Prototypical implementations are an important ingredient for potential evaluation of actual usage and acceptance before implementing a live system.
SIGMOD'15, May 31-June 4, 2015, Melbourne, Victoria, Australia. ACM 978-1-4503-2758-9/15/05. http://dx.doi.org/10.1145/2723372.2764945. Table 1 : 1 Common graph-pattern queries. ...doi:10.1145/2723372.2764945 dblp:conf/sigmod/PerelmanR15 fatcat:oj3xpmy3bjdizghurksd3uei24
In this paper, we present EAGr, a system for supporting large numbers of continuous neighborhood-based ("ego-centric") aggregate queries over large, highly dynamic, rapidly evolving graphs. Examples of such queries include computation of personalized, tailored trends in social networks, anomaly or event detection in communication or financial transaction networks, local search and alerts in spatio-temporal networks, to name a few. Key challenges in supporting such continuous queries includedoi:10.1145/2588555.2612182 dblp:conf/sigmod/MondalD14 fatcat:eybhvmptzfh5bflhrz52tgjaa4
more »... queries include very high update rates typically seen in these situations, large numbers of queries that need to be executed simultaneously, and stringent low latency requirements. We propose a flexible, general, extensible in-memory framework for executing different types of ego-centric aggregate queries over large dynamic graphs with low latencies. Our framework is built around the notion of an aggregation overlay graph, a pre-compiled data structure that encodes the computations to be performed when an update or a query is received. The overlay graph enables sharing of partial aggregates across different egocentric queries (corresponding to different nodes in the graph), and also allows partial pre-computation of the aggregates to minimize the query latencies. We present several highly scalable techniques for constructing an overlay graph given an aggregation function, and also design incremental algorithms for handling changes to the structure of the underlying graph itself. We also present an optimal, polynomial-time algorithm for making the pre-computation decisions given an overlay graph. Although our approach is naturally parallelizable, we focus on a single-machine deployment and show that our techniques can easily handle graphs of size up to 320 million nodes and edges, and achieve update and query throughputs of over 500,000/s using a single, powerful machine.
EOS 1 is a storage manager that has been prototyped at AT&T Bell Laboratories as a vehicle for research i n to distributed storage architectures for database systems and specially those that integrate programming languages and databases. EOS's overall goal is to provide fast and transparent access to persistent objects independent of their size and their physical location in a distributed computing environment based on a clientserver architecture. EOS objects are uninterpreted byte stringsdoi:10.1145/191839.191983 dblp:conf/sigmod/BilirisP94 fatcat:yov2hqeihnhenp4xtwsfqbj25q
more »... d byte strings which can range in size from a few bytes to gigabytes. Large objects, spanning multiple pages, can be accessed and updated transparently as if they were small objects, or via byte range operations. The byte range operations are important for very large objects such as digital video and audio because there may be memory size constraints that would make it impractical to build, retrieve or update the whole object in one big step. EOS les collect related object together and are stored in EOS databases. EOS databases are stored in one or more storage areas UNIX les or raw disk partitions. Clustering hints for the physical placement of objects in pages, les, databases and areas are also provided. Any EOS object can be named and subsequently retrieved by its name. EOS o ers extensible hashing supporting variable size keys and user-de ned hash and comparison functions. In addition, other index structures can be built by using page objects objects that expand over the entire available space of a page. EOS employs the multigranularity t wo v ersion two phase locking protocol, that allows many readers and one writer to access the same item simultaneously. The option to switch to simple 2PL is also available. EOS uses a write-ahead redo-only logging scheme that o ers short logs, fast recovery from system failures, and non-blocking checkpoints. Also, con guration les are provided that can be edited by users to customize and tune EOS performance. Finally, the EOS architecture has been designed to be extensible. Users may de ne hook functions to be executed when certain primitive e v ents occur. This allows controlled access to a numb e r o f e n try points in the system without compromising modularity.
Pre-computation and materialization of views with aggregate functions is a common technique in Data Warehouses. Due to the complex structure of the warehouse and the different profiles of the users who submit queries, there is need for tools that will automate the selection and management of the materialized data. In this paper we present DynaMat, a system that dynamically materializes information at multiple levels of granularity in order to match the demand (workload) but also takes intodoi:10.1145/304182.304215 dblp:conf/sigmod/KotidisR99 fatcat:vmte2bdifjgoxoxad37juwqasq
more »... lso takes into account the maintenance restrictions for the warehouse, such as down time to update the views and space availability. DynaMat unifies the view selection and the view maintenance problems under a single framework using a novel "goodness" measure for the materialized views. DynaMat constantly monitors incoming queries and materializes the best set of views subject to the space constraints. During updates, DynaMat reconciles the current materialized view selection and refreshes the most beneficial subset of it within a given maintenance window. We compare DynaMat against a system that is given all queries in advance and the pre-computed optimal static view selection. The comparison is made based on a new metric, the Detailed Cost Savings Ratio introduced for quantifying the benefits of view materialization against incoming queries. These experiments show that DynaMat's dynamic view selection outperforms the optimal static view selection and thus, any sub-optimal static algorithm that has appeared in the literature.
SIGMOD'14, June 22-27, 2014, Snowbird, UT, USA. Copyright 2014 ACM 978-1-4503-2376-5/14/06 ...$15.00. http://dx.doi.org/10.1145/2588555.2610503. participating workers. ... Copyrights for components of this work owned by others than ACM must be honored. Abstracting with credit is permitted. ...doi:10.1145/2588555.2610503 dblp:conf/sigmod/ParkW14 fatcat:yyb5yriyzbhutp6cjhf5w4l4fy
SIGMOD 2003 , 2003 June 9-12, 2003, San Diego, CA Copyright 2003 ACM 1-58113-634-X/03/06 ...$5.00. ...doi:10.1145/872757.872871 dblp:conf/sigmod/KoudasS03 fatcat:tjalofk6kfgbtlfzs45clpdpai
Database-as-a-service has been gaining popularity in cloud computing because multitenant databases can reduce costs by sharing off-the-shelf resources. However, due to heavy workloads, resource sharing often causes a hot spot; one node is overloaded even while others are not. Unfortunately, a hot spot can lead to violation of service level agreements and destroy customer satisfaction. To efficiently address the hot spot problem, we propose a middleware approach called Madeus that conductsdoi:10.1145/2723372.2724578 dblp:conf/sigmod/MishimaF15 fatcat:fmql5lerufb2pfyaill73hdo7y
more »... that conducts database live migration. To make efficient database live migration possible, we also introduce the lazy snapshot isolation rule (LSIR) that enables concurrently propagating syncsets, which are the datasets needed to synchronize slave with master databases. Madeus provides efficient database live migration by implementing the LSIR under snapshot isolation. Unlike current approaches, Madeus is pure middleware that is transparent to the database management system and based on commodity hardware and software. To demonstrate the superiority of our approach over current approaches, we experimentally evaluated Madeus by using PostgreSQL with the TPC-W benchmark. The results indicate that Madeus achieves more efficient live migration than three other types of middleware approaches, especially under heavy workloads; therefore, it can effectively resolve hot spots.
doi:10.1145/564691.564783 dblp:conf/sigmod/PhanN02 fatcat:6uui6dva4bdppm4j2zwbsxiic4
SIGMOD 2003 , 2003 June 9-12, 2003, San Diego, CA. Copyright 2003 ACM 1-58113-634-X/03/06 ...$5.00. ...doi:10.1145/872757.872851 dblp:conf/sigmod/AgichteinG03 fatcat:52zsrzqlqvbp3gca3sg3f2dfai
SIGMOD 2004 June 13-18, 2004, Paris, France. Figure 1 : 1 Plan for example query contains a packet identifier pid and the packet's size. ...doi:10.1145/1007568.1007702 dblp:conf/sigmod/BabuW04 fatcat:4dajzs6cazek3hvnoqpsu2klie
We demonstrate XRPC, a minimal XQuery extension that enables distributed querying between heterogeneous XQuery engines. The XRPC language extension enhances the existing concept of XQuery functions with the Remote Procedure Call (RPC) paradigm. XRPC is orthogonal to all XQuery features, including the XQuery Update Facility (XQUF). Note that executing xquf updating functions over XRPC leads to the phenomenon of distributed transactions. XRPC achieves heterogeneity by an open SOAP-based networkdoi:10.1145/1376616.1376768 dblp:conf/sigmod/ZhangB08 fatcat:rxsrv7tgnvfq5cijwia5ngsa2q
more »... OAP-based network protocol, that can be implemented by any engine, and an XRPC Wrapper that allows even XRPC-oblivious XQuery engines to handle XRPC requests efficiently. XRPC is fully implemented in the open-source MonetDB/XQuery engine, and is demonstrated here to co-operate with Saxon, Galax and X-Hive through the XRPC wrapper. This demonstration will focus on the following features of XRPC: (i) glue-less interaction between AJAX style webbased applications with XQuery databases thanks to the SOAP-based nature of the XRPC network protocol, (ii) the efficiency of XRPC communication also for voluminous interserver communication thanks to the Bulk RPC feature that optimizes network communication and exposes set-at-a-time opportunities to the underlying XQuery engines, (iii) the interoperability between different XQuery engines that can handle both distributed transactions (both read-only requests and updates) (iv) support and performance trade-offs of two different isolation levels for distributed transactions among different XQuery engines.
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