I don't quite understand the difference between apache solr's spell check vs fuzzy search functionality.
I understand that fuzzy search matches your search term with the indexed value based on some difference expressed in distance.
I also understand that spellcheck also give you suggestions based on how close your search term is to a value in the index.
So to me those two things are not that different though I am sure that this is due to my shortcoming in understanding each feature thoroughly.
If anyone could provide an explanation preferably via an example, I would greatly appreciate it.
Thanks,
Bob
I'm not a professional in the Solr but I try to explain.
Fuzzy search is a simple instruction for Solr to use a kind of spellchecking during requests - Solr’s standard query parser supports the fuzzy search and you can use this one without any additional settings, for example: roam~ or roam~1. And this so-colled spellcheking is used a Damerau-Levenshtein Distance or Edit Distance algorithm.
To use spellchecking you need to configure it in the solrconfig.xml (please, see here). It gives you sort of flexibility how to implement spellcheking (there are a couple of OOTB implementation) so, for example, you can use another index for spellcheck thereby you decrease load on main index. Also for spellchecking you use another URL: /spell so it is not a search query like fuzzy query.
Why should I use spellcheking or fuzzy search? I guess it is depended on your server loading because the fuzzy search is more expensive and not recommended by the Solr team.
P.S. It is my understanding of fuzzy and spellcheking so if somebody has more correct and clear explanation, please, give us advice how to deal with them.
I hope stackoverflow is the right part of the trinity to ask this kind of question ...
Google webmaster tools shows the keywords it considers important for my blog (blog.schauderhaft.de). But among the top 20% are all the month names (you know january and so on).
I actually have a two part question about this:
why does google think theses are important keywords?
how do I fix that?
It might have something to do with the whole list of archives in the head of your page: <link rel='archives' title='January 2008' and so on.
Do you think this will actually be a problem? These people don't seem to think so..
We used to have a big problem on one of our client websites with a similar problem country names appearing most important. On some pages we were running multiple forms where one could choose a country. Google was finding this all over the place and thus considered it important.
So if you have month names in archives/in dates of articles it might very well be a possibility. You have to ensure you tag each one properly if its a date you can maybe use the HTML5 code to identify that its a date; otherwise in case of archives what you can do is load this using AJAX; or calculate it using javascript.
In order to drop the counry names we had to use a jQuery trick to insert these dynamically into the page following page load. (so google no longer sees the list as important to our website)
In a typical business application it is quite common to have forms that are used for searching.
Some basic features are:
A pane that contains the search criteria
A grid to display the results
Sorting on the grid
A detail page that opens when an item is selected in the results grid
What other features would you expect in a business application's search functionality?
Maybe it's a bit trite but there is some sense in this picture:
removed dead ImageShack link
Do it as it shown at the second example, not as at the 3rd one.
There is a well known extreme programming principle - YAGNI. I think it's absolutely appliabe to almost any problem. You always can add something new if it's necessary, but it's much more difficult to remove something what is already exist because someone already uses it even if it's wrong.
How about the ability to save search criteria, in order to easily re-run a search later. Or, the ability to easily, cleanly, print the list of results.
If search refining is allowed (given a search result, limited future searches to the current results), you may also want to add a breadcrumb system, so that the user can see the sequence of refinements that lead you to the current result-set -- and by clicking on a breadcrumb, return to a previous refinement stage.
Faceted search:
(source: msdn.com)
This is displayed in the area in the right ellipse. There are filters and the engine shows the number of results that will remain after aplying the filter. This is very useful and can be done without pain in some search engines, such as Apache Solr. Of course, implement this only if filters make sense in your task.
Aggregate summary info, like total(s), count(s) or percentages.
One or more menus, like right click context for the grid, a ribbon or menu on top.
Your list for the UI elements is kinda good. Export, print (asking them whether it is really necessary to print this?), category/tag and language selection is worth to consider. Smart and working pagination (don't forget ordering).
Please do not force a search to open in a new (or even worse, always in the same window). Links of search results should be copy-pastable (always use GET),
But it really matters to have a functional (i.e. a really good) algorithm. Mostly I google company websites, because their search engine is, cough, awwwwkward. Looking for a feature chart, technical spec, pricing etc. one is not interested in press releases and vica-versa.
Search engine providers offer integration into company websites.
Use Auto-complete wherever possible on your text input fields.
If using selects or combo boxes with related information try and use chain selects to organise the information.
Where results depend on location try and serve relevant results.
Also remember to keep the search form as simple as possible even down to one text field. To refine the search you can have an alternate form as an "Advanced Search interface".
Printing, export.
A grid to display the results
Watch out not to display results a user is not authorized to see (roles / permissions / access rights).
A detail page that opens when an item is selected in the results grid
In case a user attempts to circumvent the search page links and enter some document directly, again, check out for permissions.
Validation, validation, validation.
It should be very hard, near impossible, for me to run a query that makes no sense. ie, start date occurring after an end date.
Export a numerical dataset (even if it only has one numeric column - so just make it so by default) to CSV for import into Excel (people love this function, even if only 1% of users seem to use it with any regularity. Just ask yourself when's the last time you highlighted something for copy-n-paste. Would it have been easier to open a CSV?
Refinable searches (think Google's use of site: -). People who use the search utility a lot will appreciate this. People who don't won't know it's not there.
The ability to choose to display 1 records, 5 records, 100 records, 1000 records, etc. "Paging" I believe is what we most commonly call it ;).
You mentioned sortable grids. Somebody else mentioned auto-sum or auto-count. Those are good if (once again) you have largely numeric data. But those are almost report-oriented functions.
Hope this helps.
One thing you can do is have a drop down of most common searches in plain english. e.g. "High value sales in New York in last 5 days". This is the equivalent of user selecting an amount, the city, date ranges etc. done conveniently for them.
Another thing is to have multiple search criteria tabs based on perspective of the user. Like "sales search", "reporting search", "admin search" etc.
ALso consider limiting the number of entries retrieved in the search and allow users to do more narrow searches. This depends on the business needs however.
The most commonly used search option listed first and in a prominent location.
I think your requirements are good. Take a cue from Google. Google got it right. One text box where you type whatever you want, and your engine spits out the answers. Most folks will try this, and if the answers are good enough, then that is what they will use. In the back-end, you'll probably want to flatten all of the data into a big honkin' table and then index it or use a SQL query with "LIKE" in it.
However, you will probably want to allow the user to refine the search. For this, have a link to "Advanced Search" and use a form there to specify filter criteria. This lets the user zero in on the results if basic search is not good enough. For the results on th is page, you will certainly want to have sorting on key fields, but do it after you have produced the initial result set.
It depends on the content that you are searching for.. make it relevant :) Search always look easy but can be incredibly difficult to get right.
Not mentioned yet, but very important I think - a search that actually works. This item is often neglected and makes the rest a bit moot.
I have three databases that all have the contents of several web pages in them. What would be the best way to go about searching all three and having the most relevant web page at the top of the search results?
The only way I can think of is break down content by word count and/or creating a complex set of search rules to give one content priority over another. This might be more trouble than what it's worth, but I was wondering if anybody knows a way or product out there that would be able to help me.
To further support Ivans answer above Lucene is the way to go. You haven't mentioned what platform you're on so I'll point out that you can use a .NET port of this too.
If you do use Lucene there is a very good book from Manning on the subject which I recommend you look at.
When it comes to populating your index, you have a couple of choices. For starters you can just dump all of your text into the index and allow the engine to just search on it. However, I'd recommend adding fixed fields to your index which will allow you to support things such as partitioned searches or searches against those fields only.
To explain, lets say you have a field for the website. Then you can partition your index by restricting the index search to those documents that have that website in that field.
The other process is to extract points of interest from your document and allow searches on those without searching the entire index entry. Your mileage may vary with this as the lucene engine is very well written so it may simply allow you to collect your searches into more logical units which helps you with your solution.
I've done this myself and it helps when answering management questions about what exactly is searched and indexed.
HTH!
If you're using MS SQL Server then the full text search can return a ranking for you. I haven't used it, so you'll need to check the documentation or online for specifics.
How do I apply one or more field level filters on existing search results returned by lucene?
Thanks!
Ed
Bluntly, looking at your posting record, you seem to be re-asking the same or very similar question repeatedly.
For general help in the area of Lucene and Information Retrieval, Lucene in Action is excellent, and will provide you with a better grounding than the specific answers to specific questions you get here. Lucene also has excellent online documentation for whatever version you're using.