I fixed the issue by changing the code to @Basic(optional = false) @Column(name = “LastTouched”, insertable = false, updatable = false) @Temporal(TemporalType.TIMESTAMP) private Date lastTouched; So the timestamp column is ignored when generating SQL inserts. Not sure if this is the best way to go about this. Feedback is welcome.
@Entity(name = “someThing”) => this name will be used to name the Entity @Table(name = “someThing”) => this name will be used to name a table in DB So, in the first case your table and entity will have the same name, that will allow you to access your table with the same name as … Read more
A persistence context handles a set of entities which hold data to be persisted in some persistence store (e.g. a database). In particular, the context is aware of the different states an entity can have (e.g. managed, detached) in relation to both the context and the underlying persistence store. Although Hibernate-related (a JPA provider), I … Read more
There is nothing you can do about this, short of storing the database on some other service like Amazon S3. Heroku has ephemeral storage: https://devcenter.heroku.com/articles/sqlite3#disk-backed-storage However, Heroku also comes with free persistent PostgreSQL. So I would advice you to use that instead.
You can use the Web Storage API (Window.localStorage or Window.sessionStorage). Check out this article on html5doctor for a more in-depth explanation. The Web Storage API is supported by all modern browsers at this point. The read-only localStorage property allows you to access a Storage object for the Document’s origin; the stored data is saved across … Read more
you could set your own window name, the exact syntax escapes me right now, but you can use the current time and session id to create a unique id on window load, then use that id This would be done the same way you set a name in the javascript window.open() function, (but you can … Read more
Changed in gradle from this: kapt “androidx.room:room-compiler:$roomVersion” to this: annotationProcessor “androidx.room:room-compiler:$room_version”
PersistenceUnit injects an EntityManagerFactory, and PersistenceContext injects an EntityManager. It’s generally better to use PersistenceContext unless you really need to manage the EntityManager lifecycle manually.
Define limit and offset on the Query: return em.createQuery(query) .setFirstResult(offset) // offset .setMaxResults(limit) // limit .getResultList(); From the documentation: TypedQuery setFirstResult(int startPosition) Set the position of the first result to retrieve. Parameters: startPosition – position of the first result, numbered from 0 TypedQuery setMaxResults(int maxResult) Set the maximum number of results to retrieve.
Here are the relevant sections of the JPA 2.0 specification: 8.2 Persistence Unit Packaging … A persistence unit is defined by a persistence.xml file. The jar file or directory whose META-INF directory contains the persistence.xml file is termed the root of the persistence unit. In Java EE environments, the root of a persistence unit must … Read more