How can I check if my question is a duplicate?

Question

I am still a newbie on Stack Overflow, and I always check is my question similar with another posted before? If I believe there is no question similar to mine, I ask it, but sometimes, some of my questions were really similar to others.

Perhaps it is due to my poor English skills. I have no idea in some cases which keywords I should use to search for similar questions. How can I find similar questions? I am afraid of getting my questions closed as "duplicate".

Answer 1

My own two cents: search by the main tag and some key words.

For example, suppose you want to draw a rectangle on Canvas using pure JavaScript. The main tag is javascript and the keywords are "rectangle", "canvas" and "draw".

So you just type this into the search box: [javascript] draw rectangle canvas and in the search results, you can find it was already asked in the first results page:

Answer 2

It's good that you want to look for duplicates before you ask. However, asking a duplicate is not necessarily a bad thing. Let's say you want to do something that has a jargon name in a particular language or framework, like "render". You don't know that name so you ask about "drawing". There's already a question with a great answer but it doesn't mention drawing, just rendering. So you don't find that question in your search. You ask, and your question is marked a duplicate, and it stays as a signpost for others in the future. When they search they'll find your question which will lead them to the one with the answer.

That aside, people often ask things that have been exactly asked before. Here's how to save typing and trouble and just use the other question:

• first, search as Shadow Wizard has suggested. Especially on StackOverflow, using the [] notation around tags will help a lot, as will thinking carefully about search terms. If you're calling an API, search on that function name. If you're getting an error message with a number, search on that error number.
• second, if your search results show you a question that is similar, but not quite what you want (wrong language, or about converting A to B when you want to convert B to A, for example), read that question and check the Related link on the side. Often what you want is there. Also, look at the tags on the questions you find: is there another tag you should be adding to your search? Look at the words in the question. Should you be using some of those?
• third, when you start to ask the question, pay attention to the "your answer may already be here" box that appears between the title and the body. Many times after doing a diligent search, I found my duplicate there and just abandoned asking the question.
• fourth, when you ask, be specific and complete. If you ask just "how do I X?" when you really mean "I am trying to X, and have this code so far, but the A and B don't seem quite right to me and I wonder if I should be specifying the C when I call the D?" then you might be closed as a duplicate of "how do I X?" Asking the more complete and specific question means less chance of "closed as a duplicate" and you're more likely to get the actual answer you need.

And an semi-related tip for new users. If your question turns out to be a true duplicate - the answer you want is in the other question - do not delete it. Leave it as a signpost for others who might have worded it as you did. Even if it doesn't serve that purpose, deleting your questions can hurt your ability to ask more, so don't do that.

Answer 3

There are other issues that can cause problems when searching for duplicate answers.

For example, searching for....

[javascript] draw rectangle canvas

...will produce these search results, whereas searching for...

[javascript] draw rectangles canvas

...will produce different results.

My Recommendation

Put as much effort as possible and as effective into your search, so that you yourself are satisfied that you have not found any duplicates and that you can post your question without any bad feelings.

If A Duplicate Is Found

If somebody else finds a duplicate that matches your question, then everybody benefits from the results/duplicate:

1. You: have an idea which search terms to use the next time you are searching for duplicates and you don't have to blame yourself for not searching.

2. The Community: has the benefit of having a search result in the future, that has an alternative wording in the question, which will further provide links and hits to the stackoverflow site.

Answer 4

This is an issue that has been discussed in-depth here, here, and elsewhere. It has been said that naming things is one of the hardest things in computer science, but this goes for person-to-person communication, too. Keywords & web searches come easily for some people, but I find them more of a skill you develop through trial-and-error as well as practice.

Here's my answer to you: I encourage you to *request keyword feedback in your first few question posts in order to get better keywords, have confidence in yourself and your capabilities, and be determined to keep trying.

I haven't yet racked up much reputation through up-voted questions, edits, nor answers. However, I believe in the community, in myself, and I believe in you. Good luck my friend ~

*The point I'm trying to make here is that, you're still only asking one question. With a clear feedback request reviewers are more likely to better understand your situation, and give more precise/targeted feedback, even if the question is to be closed.