Strabon
changeset 1142:b739b7f99c4d temporals
updated Changelog
author | Konstantina Bereta <Konstantina.Bereta@di.uoa.gr> |
---|---|
date | Wed May 01 14:05:20 2013 +0300 (2013-05-01) |
parents | 25967956ea23 |
children | 57ee0bc32bb0 |
files | ChangeLog |
line diff
1.1 --- a/ChangeLog Mon Apr 29 00:49:41 2013 +0300 1.2 +++ b/ChangeLog Wed May 01 14:05:20 2013 +0300 1.3 @@ -30,6 +30,21 @@ 1.4 * Support for parsing EPSG URIs in geometry literals with datatype 1.5 geo:wktLiteral. 1.6 (bug #33: http://bug.strabon.di.uoa.gr/ticket/33) 1.7 + 1.8 + *Modified the NQUADSTranslator so that the rewritten triples are 1.9 + immediately flushed to the database once they are created. 1.10 + 1.11 + *In the N-Quads format, the fourth element is *optional*. Made proper 1.12 + modification to the storage manager to coply to the specification 1.13 + described here: http://sw.deri.org/2008/07/n-quads/. Now files in 1.14 + NQUADS format can contain quads *or* triples in order to be stored 1.15 + successfully in Strabon. 1.16 + 1.17 + *Fixed bug that occurs when storing periods having "UC" as ending 1.18 + point. 1.19 + 1.20 + *Added an initial set of tests on temporal operations in the 1.21 + testsuite module. 1.22 1.23 Tue Mar 26 13:28:26 2013 Pyravlos Team 1.24 1.25 @@ -50,6 +65,18 @@ 1.26 * Updated GeoSPARQL namespaces and fixed function names to comply with 1.27 the GeoSPARQL specification. 1.28 (bug #25: http://bug.strabon.di.uoa.gr/ticket/25) 1.29 + 1.30 + *Added preliminary tests on temporal functions in the respective 1.31 + "test" package of the runtime module. 1.32 + 1.33 + *Added option to strabon and endpoint scripts to support storing 1.34 + files in NQUADS format. 1.35 + 1.36 + *When a large file in NQUADS format is going to be stored, it is 1.37 + partitioned and stored in parts. This happens because the translation 1.38 + of quads to triples is a memory intensive job, so, translating and 1.39 + storing the file in batches increases performance. 1.40 + 1.41 1.42 Wed Jan 09 18:06:41 2013 Pyravlos Team 1.43 1.44 @@ -74,6 +101,24 @@ 1.45 1.46 * Modified the names of the stSPARQL extension functions that 1.47 utilize the minimum bounding boxes of the involved geometries. 1.48 + 1.49 + *Fixed bug in the evaluation of temporal constructs. 1.50 + 1.51 + *Fixed a major bug that occured when a temporal variable that also took part 1.52 + in a temporal join was projected. 1.53 + 1.54 + *Renamed temporal extension functions to comply with the respective 1.55 + functions of Allen's temporal relations. 1.56 + 1.57 + *Modified the implementation of the temporal relation functions 1.58 + "meets", "starts", "finishes", to comply with the semantics of the 1.59 + respective functions of Allen. These functions are not supported by 1.60 + PostgreSQL Temporal, so, in order to be evaluated in the database 1.61 + level, we implemented them as PostgreSQL extension functions. 1.62 + ATTENTION: In order to use these functions, the respective sql script 1.63 + that includes them should be loaded to the the temporally (and spa- 1.64 + tially) enabled database. 1.65 + 1.66 1.67 Tue Dec 11 19:33:45 2012 Pyravlos Team 1.68 1.69 @@ -86,29 +131,62 @@ 1.70 1.71 * Version 3.2.5 released. 1.72 1.73 - * Added support for querying temporal information. This functionality 1.74 - may be found in the `temporals' branch. 1.75 + * Added support for storing and querying temporal information. 1.76 + This functionality may be found in the `temporals' branch. 1.77 1.78 - The datatypes <http://strdf.di.uoa.gr/ontology#period> and 1.79 + *The datatypes <http://strdf.di.uoa.gr/ontology#period> and 1.80 <http://www.w3.org/2001/XMLSchema#dateTime> are used to 1.81 - represent periods and instants respectively. 1.82 + represent periods and instants respectively. 1.83 1.84 - The valid time time of triples is represented using quadtruples, 1.85 + *The valid time time of triples is represented using quadtruples, 1.86 with the valid time annotation(instant or period) being the 1.87 - fourth element of the quad. In the same way, temporal triple 1.88 - patterns are used in queries to retrieve the valid time of 1.89 - triples. 1.90 - 1.91 - Some functions have been renamed (their URIs have changed) to 1.92 - follow the names of the respective relations of Allen's 1.93 - interval algebra and other functions have been added. 1.94 - 1.95 - The following temporal functions are supported: 1.96 - during, periodOverlaps, equalsPeriod, nequalsPeriod, adjacent, 1.97 - before, after, overleft, overright, meets, starts, finishes, 1.98 - period_intersect, period_union, preceding_period, and 1.99 - succeeding_period. 1.100 - 1.101 + fourth element of the quad. Into this direction: 1.102 + *Strabon has been extended to support the NQUADS format. The 1.103 + respective Sesame packages (of version 2.6.9) that support 1.104 + this format are used. 1.105 + 1.106 + *NQuadTranslator class has been created. This class uses the 1.107 + NQUADS parser which is available here: https://github.com/joshsh/sesametools/tree/develop/nquads. 1.108 + The initial version of this parser did not include support 1.109 + for literals as the fourth element of the quad. We exteded 1.110 + it to support the valid time representations described above. 1.111 + 1.112 + *The NQUADSTranslator translates quads into triples using the 1.113 + named graph approach, similar to the one proposed by Tappolet 1.114 + et al. and described in http://dl.acm.org/citation.cfm?id=1561565. 1.115 + 1.116 + *The rdbms level of Strabon has been extended to (i) support 1.117 + tha period datatype (ii) store the period values in the table 1.118 + period_values(id, period). The period column is of the period 1.119 + datatype, offered by the PostgreSQL Temporal extension (http://sourceforge.net/projects/pgsql-temporal/). 1.120 + Also, a GiST index is created on this column. 1.121 + 1.122 + *A rewriting mechanism that converts quad graph patterns into 1.123 + triple partners using the named graphs approach has been 1.124 + implemented as a method of the runtime.generaldb.Strabon 1.125 + class. 1.126 + 1.127 + *A big part of the temporal functions of stSPARQL has been 1.128 + imlemented. These functions include: 1.129 + *The temporal relation functions during, periodOverlaps, 1.130 + equalsPeriod, nequalsPeriod, adjacent, before, after, 1.131 + overleft, overright, meets, starts, finishes. 1.132 + 1.133 + *The period constructors period_intersect, period_union, 1.134 + preceding_period, and succeeding_period. The last two 1.135 + constructors are implemented using the jtemporal library. 1.136 + The other functions are implemented in the database, 1.137 + being mapped into the respective functions of PostgreSQL 1.138 + Temporal. A complete reference of PostgreSQL Temporal 1.139 + can be found here: http://temporal.projects.pgfoundry.org/reference.html. 1.140 + 1.141 + *The temporal constants "NOW" and "UC" (Until Changed) 1.142 + are supported. 1.143 + 1.144 + *The vocabulary of the valid time dimension of stSPARQL can 1.145 + be found at the TemporalConstants class of the evaluation 1.146 + module. 1.147 + 1.148 * Changed behaviour of Strabon and Strabon Endpoint for connecting to 1.149 a spatially-enabled database. Only one instance of Strabon is allowed 1.150 at a time.