I need to store the rdf schema in one table and rdf instance data in another table in ORACLE.
How I can do this?
How to configure the joseki-config.ttl to work for multiple models? Some example will help me to understand the solution.
Is there any possibility to create a single model for multiple tables?
Please let me know.
You need to use SDB with Joseki and Oracle. Then you can have a persistent datasets (a collection of models). There is an example of an SDB configuration in the Joseki download in joseki-config-sdb.ttl.
SDB controls the database table layout. A model is stored in the default graph name or in the named graphs table. There is no control for other layouts without changing the code of SDB.
Note that TDB, a custom database layer for Jena, scales better and is faster than using a relational database over JDBC. Fuseki is the new version of Joseki.
The Jena user mailing list is jena-users#incubator.apache.org.
Related
I created a multidimensional data model in SAP HANA as a calculation view type Cube with star join. In this calculation view I only used calculation views type Dimension, which include the dimension tables and the necessary changes I made to them (e.g. building hierarchies).
I now need to present a conceptual data model with all the dependencies. In PowerDesigner it is possible to reverse engineer physical data models, but when I try to do as it is described by SAP I get the physical tables as a result without the connections. I imported all calculation views and the necessary tables.
Does this happen because I did not connect the tables itself and only the views and is there a way to solve this?
Thank you very much for reading this. :)
SAP PowerDesigner can read the SAP HANA information models online help: Calculation Views (HANA).
This allows for impact analysis, i.e. the dependencies to source tables and views are captured.
However, the SAP HANA information views are usually not considered part of a logical data model as they are rather parts of analytical applications.
As for the lack of join conditions in the reverse engineered data model: if the model is reversed from the database runtime objects, that is the tables and views currently in the database, then you won't commonly find that foreign key constraints are implemented as database constraints.
Instead, SAP products implement the join definition either in the application layer (SAP Netweaver dictionary) or in the repository via view definitions and CDS associations.
See PowerDesigner and HANA for details on this.
I was looking for the best way to capture historical data in HANA for master data tables without the VALID_TO and VALID_FROM fields.
From my understanding, we have 2 options here.
Create a custom history table and run a stored procedure that populates this history table from the original table. Here we compromise with the real-time reporting capability on top of this table.
Enable the History table flag in SLT for this table so that SLT creates this as a history table which solves this problem.
Option 2 looks like a clear winner to me but I would like your thoughts on this as well.
Let me know.
Thanks,
Shyam
You asked for thoughts...
I would not use history tables for modeling time dependent master data. That's not the way history tables work. Think of them as system versioned temporal tables using commit IDs for the validity range. There are several posts on this topic in the SAP community.
Most applications I know need application time validity ranges instead (or sometimes both). Therefore I would rather model the time dependency explicitly using valid from / valid to. This gives you the opportunity e.g. to model temporal joins in CalcViews or query the data using "standard" SQL. The different ETL tools like EIM SDI or BODS have also options for populating such time dependent tables using special transformations like "table comparison" or "history preserving". Just search the web for "slowly changing dimensions" for the concepts.
In the future maybe temporal tables as defined in SQL 2011 could be an option as well, but I do not know when those will be available in HANA.
I have created a connection to the database in a SQL developer. Now in there I can see lots of Table having different dependencies and constraints applied. now its very confusing and time consuming to see the details of each table manually. I want them in a way(GUI) so that I can easily Identify that particular table is master one and all the dependencies of all other tables. does it provide any kind of tool ? or is there any other Method ?
You can generate an ER diagram for the objects and their relations.
File -> Data Modeler -> Import -> Data Dictionary
Choose the database and schema which contains the objects.
Choose the objects
I have the following question
First, I have an Sql Server (MyServer), where I have two different databases (databaseOne, databaseTwo).
Then, I'm working in a ASP.NET MVC 4 project, and this is what I want to do:
I want to create my Model with all the tables from databaseOne, but also add in the same model all the tables from databaseTwo.
All I want is all my tables in the same context because I need to do several joins between databaseOne and databaseTwo. How can I accomplish this?
I have already created my Model for databaseOne, but how can I add all the tables from databaseTwo?
The only way to do this is to create views in db1 which make the joins between db1's own tables and the tables required in db2. You can then get the views in the model.
To update the tables in db2 I don't think is possible, but you can certainly read them via views in db1.
I have a database name Team which has 40 tables . How can I connect to that database and refer to particular table without using sqlquerry. By the use of R data Structures.
I am not sure what do you mean with "How can I connect to that database and refer to particular table without using sqlquerry".
I am not aware of a way to "see" DB tables as R dataframes or arrays or whatever without importing the tuples first through some sort of query (in SQL) - this seems to be the most practical way to use R with DB data (without going to the hassle of exporting these as .csv files first, and re-read them in R).
There are a couple ways to import data from a DB to R, so that the result of a query becomes a R data structure (including proper type conversion, ideally).
Here is a short guide on how to do that with SQL-R
A similar brief introduction to the DBI family