- From: Eric Prud'hommeaux <eric@w3.org>
- Date: Tue, 2 Mar 2010 10:23:43 -0500
- To: public-rdb2rdf-wg@w3.org
On Sunday, I taugh FeDeRate to generate views (one page of code). http://dvcs.w3.org/hg/FeDeRate/file/636ceb7f6d4d/src/main/scala/SparqlToSparqlToSql.scala#l14 An accompanying test demonstrates the efficacy. http://dvcs.w3.org/hg/FeDeRate/file/636ceb7f6d4d/src/test/scala/SparqlToSparqlToSqlTest.scala#l69 Given some DDL: [[ CREATE TABLE Employee (empid INT, PRIMARY KEY (empid), firstName STRING, lastName STRING, birthday DATE, manager INT, FOREIGN KEY (manager) REFERENCES Employee(empid)); CREATE TABLE Tasks (taskid INT, PRIMARY KEY (taskid), name STRING, lead INT, FOREIGN KEY (lead) REFERENCES Employee(empid)); CREATE TABLE TaskAssignments (id INT PRIMARY KEY, PRIMARY KEY (id), task INT, FOREIGN KEY (task) REFERENCES Tasks(taskid), employee INT, FOREIGN KEY (employee) REFERENCES Employee(empid)); ]] and a configuration rule: [[ PREFIX foaf : <http://xmlns.com/foaf/0.1/> PREFIX empP : <http://hr.example/DB/Employee#> CONSTRUCT { ?who a foaf:Person . ?who foaf:first_name ?fname . ?who foaf:last_name ?lname } WHERE { ?who empP:firstName ?fname . ?who empP:lastName ?lname } ]] it emits an SQL triples view: [[ CREATE VIEW triples AS SELECT "<http://xmlns.com/foaf/0.1/Person>" AS O, "<http://www.w3.org/1999/02/22-rdf-syntax-ns#type>" AS P, CONCAT("http://hr.example/DB/", "Employee", "/", "empid", ".", R_S.empid, "#record") AS S FROM Employee AS R_S WHERE (R_S.firstName IS NOT NULL) AND (R_S.lastName IS NOT NULL) UNION SELECT CONCAT("'", R_S.firstName, "'^^<http://www.w3.org/2001/XMLSchema#string>") AS O, "<http://xmlns.com/foaf/0.1/first_name>" AS P, CONCAT("http://hr.example/DB/", "Employee", "/", "empid", ".", R_S.empid, "#record") AS S FROM Employee AS R_S WHERE (R_S.empid IS NOT NULL) AND (R_S.firstName IS NOT NULL) UNION SELECT CONCAT("'", R_S.lastName, "'^^<http://www.w3.org/2001/XMLSchema#string>") AS O, "<http://xmlns.com/foaf/0.1/last_name>" AS P, CONCAT("http://hr.example/DB/", "Employee", "/", "empid", ".", R_S.empid, "#record") AS S FROM Employee AS R_S WHERE (R_S.empid IS NOT NULL) AND (R_S.lastName IS NOT NULL) ]] -- -ericP
Received on Tuesday, 2 March 2010 15:24:17 UTC