I have googled so much how to save data persistent (meaning it is still there after I shutdown / restart my apllication).
But every guide there is is "Hey we show you how to use spring-boot with jpa real quick and we use h2 database (in-memory)"
I am looking for a guide who shows the setup to make it possible to use a database that stores the data somewhere that it can be retrieved at any later point in time, even after the application was shut down.
If any of you can provide a link to something like this, I am very grateful!
I think Google can give a lot of examples about that. I am not sure what was your query.
Here are some examples:
https://www.mkyong.com/spring-boot/spring-boot-spring-data-jpa-mysql-example/
https://www.callicoder.com/spring-boot-rest-api-tutorial-with-mysql-jpa-hibernate/
https://spring.io/guides/gs/accessing-data-mysql/
HTH
Related
I have a use case wherein I need to fetch data from GCP BigQuery database into my Springboot application and subsequently perform some operations on it. I'm unable to understand how to go about doing it. For example, how the application properties need to be configured for using BQ database, etc, nor was I able to find any good resource for the same.
Request you all to kindly guide me a bit on this. Would be great even if you could point me to a relevant resource!
Indeed there are no examples on Spring Cloud documentation. However there is nice sample on spring-cloud-gcp github.
There is small tutorial how to run it, so I think this will be good starting point.
I´m developing a Jokenpo Game using React with Spring Rest, but I can´t have a database to store all the information needed(create and delete moves, create and delete players).
I don´t know the best practice of development, or if there is some design pattern on how to store that kind of information. I know there is the folder src/main/resources where maybe I can store a text file there and thought about on the startup of the api it loads that file with the begin of the game, maybe, and after changing it during the game.
Trying to be more clear: I just would like to know the simplest way of storing information without being a database inside of a Spring Rest application. I really appreciate any helps. Thanks.
Take a look at SQLite. It's a very light database library that you can include as a dependency of your Spring application, It doesn't require a separate database server to run, and the entire database is stored in a single file, that you can choose where to store in the connection string.
It offers the flexibility of a standard database, so you can use Spring Data / JPA to access the data. It has some limitations compared with robust databases like MySQL, specially related with concurrent writes that you should investigate and be aware of. Usually it works very well for small applications or embedded applications.
I don't mean using coherence. I am looking for a way to avoid hitting my application to look something up that I've already looked up. When the client performs a GET on a resource I want it to hit the application the first time only and after that return a cached copy.
I think I can do this with apache and mod_mem_cache, but I was hoping there was a weblogic built in solution that I'm just not able to find.
Thanks.
I don't believe there's inbuilt features to do that across the entire app server, but if you want to do it programmatically, perhaps CacheFilter might work.
I'm trying to build a shopping-cart-like webapp on GAE. So far, I haven't deployed anything on GAE still and just keep doing some POC locally... then, I read this:
http://borglin.net/gwt-project/?page_id=688
It surprised me when I read through those "weaknesses" and I'm pretty worried about whether it's a good choice putting the app on GAE. Would someone, esp who has experience building a real-world app with cash transactions, please give me some ideas/share your thoughts?
The article said GAE has "No https support for your domain". Is it true? I thought what I need to do is just point my domain https://www.abc.com to GAE https://abc.appspot.com ...
For BigTable, I understand it would be quite hard to build analytic/statistical functionalities in my app (e.g. provide a monthly transaction summary). Does anyone has any experience to handle such situation...? export data from BigTable to RDBMS and do some SQL ...?
The articale also said that BigTable has a bad write performance: "I'm lucky to get 100 writes per second in a GAE request. " Is it true? I cannot find any figure to support/disprove it ..
I'm now using SpringMVC + Objectify at server-side. Is it too heavy for GAE ? Some said Spring could make a long cold start ... how cold is it? How long would it take to init an app with like, 20+ different pages/controllers, and 20+ kinds of entities/DAO ..?? Any ballpark figure ..??
p.s. If you know any real world app built on GAE, please kindly share here? Because I wanna know how far (or how big) my app could be.
Thanks a lot!
1) That is true. https is only supported for .appspot.com. A very big shortcoming.
2) That's not really true, you can do any kind of monthly summary reports using the remoting api if you need to do complex joins and such. You can also export the data and use an offline tool
3) I haven't seen that kind of write performance bottleneck, but there is eventual consistency to deal with. That said, 100 writes/second is not a small number...
4) I would avoid spring on appengine. A lot of people use it happily but I found that startup time was very slow and that caused problems.
The SSL for Custom Domains is in testing phase. Please note that HTTPS/SSL was not designed to work on shared-IP hosting (such as GAE), so there are some SSL extensions that have various support on browsers (SNI/VIP).
Queries are quite weak on Datastore. They are also expensive. There are two ways to do analytics:
a. Create a set of sharded counters and update the counter every time an event happens (= a financial transaction). We use this and is works well. The only downside is that this is "online" analytics. You can not add additional analytics parameters for the past data.
b. Upload (anonymized) data to Google Big Query and do analytics there.
Datastore has a limitation of about 5 writes-updates/s to a SINGLE entity or entity group (some sources say 1 w/s). There is no limitation on parallel writes to different entities. Remember, GAE is a distributed system where all apps use ONE BigTable database under the hood. So this is pretty scalable.
I don't have experience with this, but there are various reports on the net. See this http://www.listry.com/blog/2010/03/google-app-engine-cold-start-guide-for
I dont know about other topics, but what I can tell you is that we use a combination of Guice + jersey to substitute Spring :) its better for GAE if we take into account rhe startup time
I'm interested in the best practice to query the performance state of the mongo cluster (on mongohq) using a ruby script.
I would like to build some ruby script that checks if the mongo is idle (or near idle) and if so, start to do some work (lots of queries and updates) on it.
I suggest instead of writing this yourself to have a look at MMS. MongoHQ supports this for their dedicated database plans. See https://mms.10gen.com/docs/faq for information.
If you really want to do this yourself, you need to call the serverStatus command.
Dru:
Also, there are some additional tools that MongoHQ can make available to you. Please drop the team a note and they can give you some things to try out. But yes, as was stated above, MMS is a good solution as well.
Jason
MongoHQ