Can someone help me understand how to expose the SYS schema objects of a JBoss Teiid Virtual Database when connected via an ODBC-JDBC bridge ?
The client is connecting to ODBC side of the bridge and the JDBC side of it is connecting to the Virtual Database (VDB) running on the JBoss SOA server.
With the current setting only the tables and columns modeled thru the JBoss Studio's Teiid Designer are exposed but not the SYS schema and its underlying objects. Client App is Microstrategy BI application.
You are able to traverse all metadata from all used data sources using native JDBC JAVA API.
I am new to Teiid and had the similar question.
When you create the VDB with JBoss designer you can specify which models will be exposed to the client applications. As a good practice, only View models are exposed and Source models are not. As a result, querying against the System tables of the VDB will only show you the metadata within the View models, which will be a subset of the metadata in the underlying data sources.
Hope this helps.
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I am using AxonIQ AxonFramework version 4.5.3 with Spring Boot and custom event store.
I'm using MongoEventStorageEngine and configured a separate MongoDB database for the EventStorage.
I am doing some business logic with my business database through a microservice. In the same microservice, I've configured the custom EventStorage.
But a few tables (viz. association_value_entry, saga_entry, token_entry) are getting created on my business database which is a PostgresDB.
Why is AxonFramework creating new tables in my business database as I have already configured a separate MongoDB database for EventStorage. All the related database objects for Axon to work should be ideally created in the EventStorage database rather than in my business database.
The tables you are mentioned should be part of your 'read' model (I believe that is what you called business database).
They are not used for Event Storage or Event Sourcing but rather to specific things that are controlled on client side. For example, token_entry, among other things, is the table where your app keep track of the tokens and events it already consumed - you can read more about it here. Similar to the saga tables, where Sagas are stored on the client side having nothing to do with the Event Store - you can read more about it here.
I am working on a GraphQL with Java, my concerns is will GraphQL supports oracle as Database engine or is it only supports document based databases like Mongo and Graph DataBases?
is it only supports document based databases like Mongo and Graph
DataBases?
No. GraphQL is not another NoSQL. It has nothing to do with what database you use. You can use whatever you like or even calling another web service to store/get data.
I have a gemfire cache v8.2.1 from which I want to access data using a third party tool which can only access data using jdbc driver only. Does anyone know how can I connect to gemfire cache for accessing data using jdbc? I don't require to write to cache, just want to read from the cache.
I came across with gemfirexd on internet but can see that its marked as "End of availability".
Is there any other way where persisted Objects can be retrieved or OQL can be fired but can mimic a jdbc driver so that the any tool that accepts only jdbc drivers can be used?
Please help.
Thanks
Apache Calcite has a Geode adapter that enables you read data from GemFire over JDBC. There is also this video explaining this.
Airpal currently uses presto client to connect to PrestoDB. However as I understand, it can also use JDBC for this connectivity. Is there any code available for this purpose? Even if it is for connecting to any other database it might be helpful for me. The model for presto client looks a lot different than other models like JDBC etc.
Airpal is using presto client connectivity and also using these objects (mostly for schema and data like Column, QueryResults etc.) internally in its various modules.
One way for providing JDBC connectivity is to move its lowest layer of DB connectivity (executeWith invocations of com.airbnb.airpal.core.execution.QueryCliemt: there is 1 for data and about 6 for metadata) to JDBC query execution. The JDBC results (mostly data and schema) can then be converted to presto client api equivalent objects and rest of the logic in airpal would follow.
Another approach is to rewrite airpal with native JDBC support by moving over to JDBC objects for internal use and communication as well. It looks like a much bigger change.
I am planning to add support for dynamically choosing between presto client or JDBC connectivity. I will use the com.airbnb.airpal.presto.QueryRunner to hold either a presto client session or a JDBC connection accordingly.
I'm inheriting an existing WMB flow that is ESQL-centric (Compute nodes) that accesses its database via an ODBC DSN. I'd prefer to use a configurable service for database access in lieu of an ODBC DSN, which is what I use with Java-centric flows (JavaCompute nodes).
Is it possible to configure a Compute node to talk to a db via a configurable service?
Yes, but you need to call a Java class from the ESQL.
See Connecting to an application database using JDBC