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.