Skip to main content

Related Articles

Loading...

How To Specify Unique Key/Primary Key Constraints In DB2

Using iSeries Navigator you can very easily specify Unique Key and Primary Key for database table in DB2 database. Most of the people are not well aware that DB2 is relational database and it support all the relational database concepts. I have experience that most of the developers are not using key constraints, referential integrity, triggers etc. But most importantly DB2 is support for all these features. Let's look at one by one how these concepts can be implemented using iSeries Navigator on DB2 database.

To create Unique Key or Primary Key for a given table you need to go the table definition. Right click on the table that you want to modify and add new key and select "Definition" option.

Fig 1: Table Definition Option



In table definition window go to "Key Constraints" tab and click on Add button.


Fig 2: New Key Constraint Window
In New Key Constraints window specify constraint name or leave "Constraint Name" field as it is to system generated constraint name. Then select whether you want to specify unique key or primary for the table. In "Available Columns" box you will see all available columns in the table and you can select either one of them or more than one columns for composite key. Once you select column click on Add button at middle of the window to put them into "Selected Columns" box. You can change the order of columns if you have selected more than one column, by using Move Up or Move Down buttons. If everything completed click on OK button to add this constraints to the table. You can add more that one constraint for a given table as you wish. Also note that if the table is having conflicting data to create new key constraint, you might face issues while you creating these constraints. Then find the conflicting data set and correct them possible or remove them from table so that you are able to create new constraint successfully.

Comments

Post a Comment

Popular posts from this blog

The Power of ChatGPT and Whisper Models

A Deep Dive into Natural Language Processing Natural Language Processing (NLP) has seen a significant boost in recent years due to advancements in artificial intelligence and machine learning. Two models that have shown remarkable success in NLP are ChatGPT and Whisper. In this article, we will delve into the power of these models and their applications in the field of NLP. ChatGPT is a transformer-based language model developed by OpenAI that uses unsupervised learning to predict the next word in a sentence based on the context of previous words. ChatGPT is a generative model that is trained on large datasets of text, such as books and articles, and can be fine-tuned for specific tasks, such as question-answering or dialogue generation. ChatGPT is known for its ability to produce human-like text, making it an ideal tool for applications such as chatbots, content creation, and language translation. Whisper, on the other hand, is a paraphrasing model developed by Google that is based on...
Post a Comment
Read more

PrimeNG UI Components For Angular Application

Getting Started With PrimeNG Styling in Angular App  This chapter we are going to check how you can add PrimeNG card component to show available flowers in the stock. Before styling the app, I have added some images of flowers to our assets folder as below. In app.module.ts file you can import PrimeNG Card module as below. import { BrowserModule } from '@angular/platform-browser'; import { NgModule } from '@angular/core'; import { AppRoutingModule } from './app-routing.module'; import { AppComponent } from './app.component'; import { LandingComponent } from './modules/landing/landing.component'; import { HomeComponent } from './modules/home/home.component'; import { CardModule } from 'primeng/card'; ; @NgModule({   declarations: [     AppComponent,     LandingComponent,     HomeComponent   ],   imports: [     BrowserModule,     AppRoutingModule,     CardModule,        ],   provider...
Post a Comment
Read more

React Hooks

React Hooks revolutionized the way we write components in React by providing a more concise and functional approach to managing state and side effects. In this article, we will explore the basics of React Hooks, their benefits, and how they differ from traditional class components. Whether you're new to React or an experienced developer, understanding Hooks is essential for building modern and efficient React applications. React Hooks are functions that allow you to use state and other React features in functional components. They were introduced in React version 16.8 as a way to write reusable and stateful logic without using class components. Prior to Hooks, stateful logic was typically managed in class components using lifecycle methods such as componentDidMount , componentDidUpdate , and componentWillUnmount . This often led to complex and hard-to-maintain code, especially when dealing with multiple lifecycle methods or sharing stateful logic between components. With React Hook...
Post a Comment
Read more