We typically interface with a RDBMS through SQL. I.e. we create a sql string and send it to the server through JDBC or ODBC or something similar.
Are there any RDBMS that allow direct interfacing with the database engine through some API in Java, C#, C or similar? I would expect an API that allows constructs like this (in some arbitrary pseudo code):
Iterator iter = engine.getIndex("myIndex").getReferencesForValue("23");
for (Reference ref: iter){
Row row = engine.getTable("mytable").getRow(ref);
}
I guess something like this is hidden somewhere in (and available from) open source databases, but I am looking for something that is officially supported as a public API, so one finds at least a note in the release notes, when it changes.
In order to make this a question that actually has a ‘best’ answer: I prefer languages in the order given above and I will prefer mature APIs over prototypes and research work, although these are welcome as well.
—————— Update —————-
Looks like I haven’t been clear enough.
What I am looking at is a lower level API, sort of what the RDBMS probably use internally. RDBMS have the concept of an execution plan, and the API I am looking for would allow us to actually execute an execution plan without specifying the intended result, using SQL or similar.
The very vague idea behind this is to implement a DSL which translates directly to RDBMS system calls, without going through SQL or similar.
Trying to explain it in yet a different way: When e.g. Oracle gets fed with a SQL statement, it parses that statement, creates an execution plan out of it and finally executes the execution plan using some internal API, which probably allows things like: retrieving a specific row from a table, retrieving a range or rowids from an index, joining to sets of rows using a hash join and so on. I am looking for that API (or something similar for an RDBMS where this is available)
———- Another update after comment by Neil —————-
I think it would be appropriate to consider the API I am looking for the ‘ISAM’ level as in the second bullet point on this article: http://en.wikipedia.org/wiki/ISAM
The stuff I was looking for is called ISAM as correctly pointed out by Neil Butterworth.
So the wikipedia article http://en.wikipedia.org/wiki/Isam gives some points to start further research.
If you happen to find this useful please upvote Neils comment above.