It will depend on several factors, including the scope and breadth of the PhD and your subject discipline. In some fields it's common to publish a number of papers from the PhD based on separate findings/experiments. In others there may only be one main paper focusing on a key argument/point. Some people will publish from their PhD then write papers subsequently reflecting on their research or revisiting it, or exploring a particular methodological approach. In some fields writing a book from the thesis is more valued than a paper.

It's really about what makes the most sense of your data. If it's to separate it into more than one publication because the data is dense and complex with multiple findings and it's easier to understand in that way, that's appropriate to share in more than one publication. If the data is complex and best understood as one coherent paper with different aspects of the research documented in one space, then it's best to publish as a single study.

What is frowned upon is trying to take the same findings and republish them in multiple outlets, giving the impression they're from entirely different research or sneakily breaking up the study to get more publications from it when in fact it makes more sense published in its entirety. This is sometimes called 'salami slicing' and is unethical as it can be misleading for audiences and misrepresents research.

Pushing data into lots of papers for the sake of getting more publications is unethical and should be avoided. Ultimately the integrity of the research and accuracy of findings should be maintained in order to publish the research in a way that's the most useful and accurate for wider audiences to understand and use.

Petra Boynton that's a very comprehensive explanation of the question, thanks for sharing your valuable views.

You're very welcome - I'm glad it was helpful. Something to consider is a publication strategy. Particularly for those whose PhDs are being completed in disciplines where there's an expectation a publication happens (or is in press) before the viva.

Thinking about what part of the PhD is the most significant, what journal would be the best fit for it, whether other places could also develop the paper (e.g. a poster or conference presentation to get feedback prior to submitting a paper). All of that is useful. It can also help to note if you want to write a paper based on data alone, or a subsidiary paper based on explaining the methodology if that's novel, or a more reflective piece about skills learned or experiences gained during the course of undertaking the PhD.

Petra Boynton It was constructive feedback, you have rightly said that the most significant part of PhD is to remain consistent in writing research papers, posters, or conference presentations and achieve novelty in the field of research

The number of research paper that can be written in single research paper depends on the number of variables within the research topic.

Ismail Oyebanji Ajibade By exploring different dimensions of the study and employing various methods, researchers can produce multiple papers that contribute to a comprehensive understanding of the topic.