I've a .net web application which uses Lucene.net for company search functionality.
When registered users add a new company,it is saved to database and also gets indexed in Lucene based company search index in real time.
When adding company in Lucene index, how do I handle use case of two or more logged-in users posting a new company at the same time?Also, will both these companies get indexed without any file lock, lock time out, etc. related issues?
Would appreciate if i could help with code as well.
Thanks.
By default Lucene.Net has inbuilt index locking using a text file. However if the default locking mode isn't good enough then there are others that you can use instead (which are included in the Lucene.Net source code).
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My requirement is like job sites where a user can upload a document(can be PDF,Text or word document) like Resume/CV. Then all these documents can be searched for a specific or a combination of keyword and they also have to be ranked based on those key words. I need to know which technology can be good from performance point of view when the number of files are huge and also there are good number of request for searching and indexing.
The website is built using SQL Server. So can I store those files in SQL Server? Will be good in terms of performance.
Or can it be done alone using Lucene.NET and i can store those files in single folder?
I think, the best suggestion is to use Lucene ....
you can save your documents as they are with some unique path name/file_name , and use that as identifier when you index the documents ... I am sure you can find a lot of similar examples if you search Lucene ..
I don't think this is a very obscure Lucene problem, but somehow I just don't seem to be able to find a good solution to it. I will use an example.
Let's say I am building a news articles website. Registered users can bookmark articles that they are interested in. I want to allow users to search for only articles that he/she bookmarks. For the sake of example, let's also assume that a user can potentially bookmark thousands of articles, and we have hundreds of thousands of users in our database. How do I build a scalable solution for this problem?
Thanks a lot!
This is a very typical Lucene problem as it does not support joins. More specifically, there's no first class support and you have to find your ways around it. I can suggest a few:
You could have a database, which has users, articles and bookmarks tables (the latter would have foreign keys pointing to the first two). You would also have articles indexed in Lucene. When running a search against articles, you could write a Lucene Filter which would exclude all articles not bookmarked by the current user.
You could index all articles and bookmarks in Lucene - probably best if you do this using separate indices. Then you could run a query for bookmarks (to retrieve which articles current user has bookmarked) and then run another separate query for articles. Like in the previous example, you could use the results of the first query to exclude all other articles which are not bookmarked by the current user.
I personally prefer option #1 as this is classical relational structure and databases are designed for exactly this purpose. With the option #2 you would have to modify both user storage and Lucene index when user gets deleted.
I have been using Sitecore query and FAST query for some sections of the website. But with growing content these queries have gotten slow and I'd like to implement Lucene querying for content to speed up things.
I am wondering if I can just use the System index instead of having to setup a separate index. Does Sitecore by default index all content in the content editor? Is this a good approach or should I just create my own index?
(I'm going to assume your using Sitecore 6.4->6.6)
As with everything .. it depends .. Sitecore keeps an index of all the Sitecore items in its system index, you are welcome to use that. Sometimes you may want a more specialised or restricted list of items, like being based on a certain template, being indexed or need a checkbox field indexed (as the system one by default only indexes text fields).
Setting up your own search index is pretty easy.. It does require some fiddling with the web.config though (and I'd recommend adding as a .include file).
Create an new <index> node with its own id that will define the name of the collection and the folder it will go into. (You can check its working by looking for the dir in the /data/indexes directory of your installation.
.. next you can tell the crawler which database to look at (most likely master if you want unpublished content to be indexed or web for published stuff) and where to start the search from (in this example I am indexing only the news section). You can tag,boostand tell if whether to IndexAllFields (otherwise it will only index fields it understands as text .. rich-text / multi-line text / text etc).
.. Finally, you can tell the indexer which template types to include or exclude.
How the indexer works is that it will subscribed to item events within sitecore .. so every time an item is changed or moved or deleted the index will be updated automatically. Obviously if you are indexing the web db the items will need to have been published.
More in-depth info on the query syntax & indexing can be found here on SDN.
The search syntax and API is much improved in 6.4/6.5 but if you want to add extra kick then my colleague Alex Shyba's Advanced Database Crawler is worth checking out too.
Hope this helps :D
You will want to implement your own index. For the same reason that you are seeing things slow down when there is a lot of content, indexes slow down when there is a lot of content in it as well.
I prefer targeted indexes meant specifically to drive the functionality I need and only has the data in it that is required. This allows for smaller and more efficient index usage on your components.
Additionally, you probably want to look into the AdvancedDatabaseCrawler put together by Alex Shyba. There are a few blogs out there with some great posts on implementing this lucene indexing module.
A separate index is always a wise decision, you can keep it light. In big environments the system index can grow up to gigabytes.
You can exclude the content from the index, as you will only be using it for performing lookups, not showing content from the index.
Finally: the system index is for the master database, you'll be querying the web database, possibly on a content delivery server.
I've been looking for a program to create an index from static webpages. I'm not looking for a program like Solr, or elasticsearch because both are assuming I will be interactively creating an index. I need something that can basically go to a url, and create a search index from the pages that it pulls. It can create the index in whatever way necessary (db, xml, etc.) I just don't need the programs that are so involved with the backend database access and the code, as this search will be very light and mostly for internal purposes, on a site that does not use any of those.
Thanks for any tips that may get me started or answers that will solve my problem!
Investigate Nutch. Nutch can index a URL and what you can index is very configurable.
Once you finish crawling/indexing, that index is searchable. There is no programming involved.
My company has a collection of about 3500 highly-structured Word docs (and growing) that contain multiple choice questions from one of our products. I've been tasked with writing a front-end that will let people find and use these in other products. There is some metadata on them that would go in a database, but we'd also like full-text search.
I've been given the option of using for the front-end either MS Access (because I know it well) or Rails (because I'm supposed to be learning it). I've done one Rails app and prefer to continue with it.
Rather than load the documents into the database, I thought it made more sense to just have them on the file system and store paths to them in the database.
I know I can use Ferret to search database fields but what's the best way to add full-text searching to a Rails app for a pile of files on the filesystem?
Not sure if there are any gems that would search the word files for you. Although you have mentioned that you do not want to load the entire documents into the database, you might look into just copying the text contents of each file in your db. You can use win32ol library for doing this (http://ruby-doc.org/stdlib/libdoc/win32ole/rdoc/classes/WIN32OLE.html) .. If I had to implement this, I would run a cron job every night (or whatever frequency seems fit) that would refresh the database content with the changes in the word files.