My current project uses spring data couch base 1.2.3 Release version where CouchBaseClient object will be there to retrieve save/get data in key value format from couch base server/cluster/bucket. Now we are planning to upgrade spring data couch base version to 2.x, but CouchBaseClient object has been deleted in 2.x instead bucket/cluster beans are available. Bucket object doesn't have any APIs/methods to save/get data in key value format [ i might be wrong, not sure] so request to help me to find out how to proceed further is there a way in 2.x to store data in key value format?
we have plans to upgrade spring boot version to 1.4.4.release as well so if there are any others ways to interact easily with couch base server, please let me know.
My project env info:
Spring boot 1.2.3
Java 1.8
Thanks,
Satish
This is more a factor of the underlying SDK being of a different generation (2nd generation of Couchbase SDKs, where most methods align in all languages/SDKs and the whole API has been made more coherent).
This generation of SDK exposes objects closer to the reality of the Couchbase cluster: Cluster object to connect to the nodes and perform cluster-wide operations, then Bucket to perform data operations.
Spring Data Couchbase 2.x builds on that. In your configuration you'll choose which Bucket to use (see the docs) and as such you'll also be able to inject that Bucket instance if you really need to.
Note that Spring Data Couchbase offers several layers of abstraction on top of the SDK: repositories for CRUD operations around an entity type, then CouchbaseTemplate that offers individually typed operations but is still capable of marshalling to JSON (the SDK is accessible from CouchbaseTemplate).
On the other hand, with the SDK you have to marshall to JSON yourself, either as a JsonObject map-like structure (default) or a String (in which case you need to store and retreive a RawJsonDocument). Working with these Document types is all explained in the SDK's documentation.
Related
In My Application, Using the below technologies
Spring boot 2.7.x
Cassandra
spring batch 5. x
java 11
As part of this, I need to extract data from the Cassandra database and need to write out the file
so here I need to use queries to fetch data so
just want to know what is the best way to maintain all queries at one place so any query changes come in the future, I shouldn't build the app rather just need to modify the query.
Using a repository class is necessary. If you are using JPA i recommend using a repository for each Entity class. With JDBC it is possible to create a single repository which contains all the queries. To access the query methodes i would use a service class. In this way your code is structured well and maintainable for future changes.
I want to configure the CosmosQueryRequestOptions.maxDegreeOfParallelism while using the CosmosRepository. I didn't find any documentation around it.
This blog shows how to configure and use this setting through a custom client, but I want to use the repository instead. https://medium.com/#middha.nishant173/improve-query-performance-with-azure-cosmosdb-java-sdk-v4-db1fc54cb484
CosmosQueryRequestOptions is implementation detail for Spring Data Cosmos SDK, so customers cannot set it through spring application.
This can be implemented as a new feature, and can be exposed through application.properties via query.maxDegreeOfParallelism - which customers can opt in if they want.
Default value for maxDegreeOfParallelism is 0, which is the right value for single partition queries. For cross partition queries in the current SDK version, you can get the cosmosClient through spring boot applicationContext and run the query directly against the client. This example shows how to do it - https://github.com/Azure/azure-sdk-for-java/blob/main/sdk/cosmos/azure-spring-data-cosmos-test/src/test/java/com/azure/spring/data/cosmos/repository/integration/PageableAddressRepositoryIT.java#L144
There are may blog available around this but still not getting exactly what is needed.
I am trying to write a REST API with Spring Boot and store data in database. Here the database structure may change (new tables can get introduced or some existing names may get renamed).
Which DB can be used so that there would be minimal code changes needed both at java side and DB side.
What could be a best design approach in this scenario considering technology stack as Spring Boot and Azure
Please visualize about your persistent storage? Why Azure Only? Refine question.
e.g. H2 database with Spring Boot is the most memory efficient.
see Lightest Database to be packed with an application
About Minimal code changes - I'd go with one of the ORM - JPA(or Hibernate). So will only need to maintain #Entity class on java side.
Don't forget - minimal changes still need to be addressed at database & Java side.
I want to access a Neo4j DB with Java and wanted to know what the preferred way to do this is. I just want to write a quite simple data structure to the DB.
http://neo4j.com/developer/java/ gives following options:
JDBC
Hibernate OGM
Spring Data
Rest API via Unmanaged Extensions
I looked into accessing Neo4J with JDBC and Hibernate OGM. It seems that its not worth it to use for me. JDBC gives me some trouble. So should i go with the REST way or try to fix my JDBC problems?
The JDBC driver is really a wrapper around the REST interface (as of neo4j 2.3). There is a example application how to use it. Should suffice for very simple use.
Then there is neo4j-ogm (different from Hibernate OGM) - this is an object graph mapping library, similar to hibernate in ORM world. This has minimal external dependencies and is very easy to use - ideal for cases where you want to map couple of objects into graph.
Then there is the Spring Data Neo4j project, which since version 4 uses neo4j-ogm for mapping, but adds other Spring data features, like repositories, derived finder queries, transactions ...
Mule got inbuild object stores to cache data, But what is the purpose of using custom object stores under caching strategies? If possible, Please mention a usecase.
Custom object stores are useful when you want to use a custom persistence mechanism for your ObjectStore's
By default Mule provides two implementations, in-memory and a file based persistent store.
One possible use-case is, if you use Enterprise Edition have clustering enabled, you also have the ability to share these stores across multiple Mule nodes. However if you do not use EE or clustering but still want to share data between multiple Mule's, then you will need to use a persistent object store that can be shared across multiple mule nodes.
The ObjectStore interface has many implementations so you can choose a persistence mechanism that best suits you. Examples include Redis, Ehcache, Mongo, Cassandra, JDBC. More on this here:http://java.dzone.com/articles/synchronizing-data-across-mule
Ryan has given the correct explanation.. I just want to add:-
Mule uses object stores whenever it needs data to persist for later retrieval.
Custom Object store can be configure using Java classes and you can customize the Object store as per your need..
You can customize it and control your Cache and the Cache Keys, as well as store and retrieve the data, log you Cache keys and Cache contents, list you Cache keys etc from the Java class and that means full control on the Custom Object store ..
Please go through the following links :-
http://ricston.com/blog/cache-scope-ehcache/
http://java.dzone.com/articles/cache-scope-ehcache
http://www.mulesoft.org/documentation/display/current/Mule+Object+Stores