HI Michael,
While requesting Virtuoso with SPARQL via odbc (with a PHP script), we have some problems with the received format of the resultset. Without defining a result-format and with the use of the procedure DB.DBA.SPARQL_EVAL we get a odbc_resultset, which isn't really usable for us. We can fetch it into a list of objects for instance, but literals are received without language or datatype definitions. (With defining the result-format as RDF/XML, these definitions are included, but this received data structure must be parsed and wrapped in an other adequate data structure). Is there another possibility to get a complex object like an RDF-Box, a table (with included datatype or language definitions) or something else?
We have added some extensions to our virtuoso ODBC driver to get this information using the SQLGetDescField function. We are currently in the process of writing some documentation and samples to show this in more details, but here are the defines in case you want to experiment.
/******************* Virtuoso ODBC Extensions *******************/ /* * ODBC extensions for SQLGetDescField */ #define SQL_DESC_COL_DV_TYPE 1057L #define SQL_DESC_COL_DT_DT_TYPE 1058L #define SQL_DESC_COL_LITERAL_ATTR 1059L #define SQL_DESC_COL_BOX_FLAGS 1060L #define SQL_DESC_COL_LITERAL_LANG 1061L #define SQL_DESC_COL_LITERAL_TYPE 1062L /* * Virtuoso - ODBC SQL_DESC_COL_DV_TYPE */ #define VIRTUOSO_DV_DATE 129 #define VIRTUOSO_DV_DATETIME 211 #define VIRTUOSO_DV_DOUBLE_FLOAT 191 #define VIRTUOSO_DV_IRI_ID 243 #define VIRTUOSO_DV_LONG_INT 189 #define VIRTUOSO_DV_NUMERIC 219 #define VIRTUOSO_DV_RDF 246 #define VIRTUOSO_DV_SINGLE_FLOAT 190 #define VIRTUOSO_DV_STRING 182 #define VIRTUOSO_DV_TIME 210 #define VIRTUOSO_DV_TIMESTAMP 128 #define VIRTUOSO_DV_TIMESTAMP_OBJ 208 /* * Virtuoso - ODBC SQL_DESC_COL_DT_DT_TYPE */ #define VIRTUOSO_DT_TYPE_DATETIME 1 #define VIRTUOSO_DT_TYPE_DATE 2 #define VIRTUOSO_DT_TYPE_TIME 3 Patrick
