Structured Query Language with Recursion
نویسندگان
چکیده
Writing recursive queries for a database is currently a complicated task. The query requires the user to write complex and redundant SQL syntax. Also if the database being used as a backend is not compliant with SQL:1999 then it is not possible to write any recursive queries. In this paper, we present Structured Query Language with Recursion (SQLR), a data retrieval language used for writing recursive queries for any relational database, e.g. MySQL, Oracle, DB2, even the ones not using SQL:1999. We have also developed a Java package, which can be used to send recursive queries to a database (using the language presented), and receive the requested information from the database. Hence we have developed a very flexible and non-intrusive system to run recursive queries, without having to change the underlying database in any way. We have specifically tested the language on the CiteSeer database (http://citeseer.ist.psu.edu). The database was chosen because it is possible to transform it into a graph and recursive queries on this database will be useful for future research.
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