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Spring Data JPA Postgres UUID @Id

14. March 2022 | 1 min read | 2 Comments |

I read lots of outdated info on this matter. Using PostgreSQL v13+ there is a function called gen_random_uuid(). See the manual page of Postgres UUID. Here’s an example entity called Page

package de.icod.blog.model;
import javax.persistence.*;
import java.util.UUID;
@Entity
@Table(name = "page")
public class Page {
@Id
@GeneratedValue(strategy = GenerationType.AUTO)
@Column(name = "id", nullable = false, columnDefinition = "UUID default gen_random_uuid()")
private UUID id;
public UUID getId() {
return id;
}
public void setId(UUID id) {
this.id = id;
}
}

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package de.icod.blog.model;

import javax.persistence.*;

import java.util.UUID;

@Entity

@Table(name = "page")

public class Page {

@Id

@GeneratedValue(strategy = GenerationType.AUTO)

@Column(name = "id", nullable = false, columnDefinition = "UUID default gen_random_uuid()")

private UUID id;

public UUID getId() {

return id;

}

public void setId(UUID id) {

this.id = id;

}

As you see you can append the columnDefinition to the @Column annotation. “UUID default gen_random_uuid()” This translates to following SQL

create table page
(
id uuid default gen_random_uuid() not null
constraint "primary"
primary key
);

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create table page

(

id uuid default gen_random_uuid() not null

constraint "primary"

primary key

);

And you…

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Easily remember ManyToMany ManyToOne OneToMany

14. March 2022 | 1 min read | 0 Comments |

ManyToMany in a Person Blog Relationship A Person can be a subscriber of many blogs. A Blog can have many subscribers.

const Person = {
isSubscriberOfBlogs: []
}
const Blog = {
subscribers = []
}

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const Person = {

isSubscriberOfBlogs: []

}

const Blog = {

subscribers = []

}

But since this is an inefficient way to manage usually a proxy table is used with [PersonID], [BlogID], aka the 2 related data models. ManyToOne and OneToMany in a Person Blog Relationship A…

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Vue composition api: ensure variable is not null

11. March 2022 | 1 min read | 0 Comments |

I ran into a problem where I was loading data from the backend in App.vue and when loaded that data would be inserted into a vuex store and in another component queried. However the loading took longer than expected and a data race happened. The route destination rendered faster than the backend could deliver data…

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o2 DNS Auflösung mit Fehlern oder langsam

4. March 2022 | 1 min read | 0 Comments |

Es ist der 04.03.2022 seit ca. 18 Uhr funktioniert die DNS Auflösung bei O2 garnicht oder nur sehr langsam. Vor allem Google scheint probleme zu haben, aber nicht nur Google. Es ist bei mir Rechner- und Domänenübergreifend. O2 in Göppingen, welches ca. 40km östlich von Stuttgart liegt. Ich hab sie vorübergehend überbrückt mit meinem Server,…

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WordPress is the worse “shareware” model

1. March 2022 | 1 min read | 0 Comments |

WordPress basic, which doesn’t have much functionality may be free and open, but the meat of it, the plugins, aren’t. The WordPress plugin ecosystem has grown from being an useful extension framework to a monster of “shareware”, trialware only set out to make a sale. Even the spamfilter Akismet, which once used to be free…

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