I got a table with columns: author firstname, author lastname, and booktitle
Multiple users are inserting in the database, through an import, and I'd like to avoid duplicates.
So I'm trying to do something like this:
I have a record in the db:
First Name: "Isaac"
Last Name: "Assimov"
Title: "I, Robot"
If the user tries to add it again, it would be basically a non-split-text
(would not be split up into author firstname, author lastname, and booktitle)
So it would basically look like this:
"Isaac Asimov - I Robot"
or
"Asimov, Isaac - I Robot"
or
"I Robot by Isaac Asimov"
You see where I am getting at?
(I cannot force the user to split up all the books into into author firstname, author lastname, and booktitle, and I don't even like the idea to force the user, because it's not too user-friendly)
What is the best way (in SQL) to compare all this possible bookdata scenarios to what I have in the database, not to add the same book twice. I was thinking about a possibility of suggesting the user: "is THIS the book you are trying to add?" (imagine a list instead of the THIS word, just like on stackoverflow - ask question - Related Questions.
I was thinking about
soundex
and maybe even the
like
operators, but so far i didn't get the results i was hoping.
You can implement significantly better algorithms for fuzzy matching than soundex/difference, take a look at Beyond SoundEx - Functions for Fuzzy Searching in MS SQL Server.
You could also look at implementing a Full Text catalog and using the "search engine" style FREETEXT() which:
Is a predicate used in a WHERE clause
to search columns containing
character-based data types for values
that match the meaning and not just
the exact wording of the words in the
search condition
Depending on what your doing you could also perhaps use an ISBN web service to get normalized data.
Related
I'm using Lucene 4.10.3 with Java 1.7
I'm wondering whether it's possible to order query results the matching term?
Simply put, if my documents conatin a text field;
The query is
text:a*
I want documents with ab, then ac, then ad etc.
The real case is more complex however, what I'm actually trying to accomplish is to "stuff" a relational DB into my lucene Index (probably not the best idea?).
An appropriate example would be :
I have documents representing books in a library. every book has a title and also a list of people who has borrowed this book and the date of borrowing.
when a user searches for a book with title containing "JAVA", I want to give priority to books that were borrowed by this user. This could be accomplished by adding a TextField "borrowers", adding a SHOULD clause on it and ordering by score)
also, if there are several books with "JAVA" that this user has borrowed before, I want to show the most recent borrowed ones first. so I thought to create a TextField "borrowers" that will look like
borrowers : "user1__20150505 user2__20150506" etc.
I will add a BooleanClause borrowers: user1* and order by matching term.
any other solution ideas will be welcome
I understand your real problem is more complex, but maybe this is helpful anyway.
You could first search for Tokens in the index that match your query, then for each matching token executing a query using this token specifically.
See https://lucene.apache.org/core/6_0_1/core/org/apache/lucene/index/TermsEnum.html for that. Just seek to the prefix and iterate until the prefix stops matching.
In general it is sometimes easy to just issue two queries. For example one within the corpus of books the user as borrowed before and another witin the whole corpus.
These approaches may not work, but in that case you could implement a custom Scorer somehow mapping the ordering to a number.
See http://opensourceconnections.com/blog/2014/03/12/using-customscorequery-for-custom-solrlucene-scoring/
I have a full text indexed table in SQL Server 2008 that I am trying to query for an exact phrase match using FULLTEXT. I don't believe using CONTAINS or LIKE is appropriate for this, because in other cases the query might not be exact (user doesn't surround phrase in double quotes) and in general I want to flexibility of FREETEXT.
According to the documentation[MSDN] for FREETEXT:
If freetext_string is enclosed in double quotation marks, a phrase match is instead performed; stemming and thesaurus are not performed.
which would lead me to believe a query like this:
SELECT Description
FROM Projects
WHERE FREETEXT(Description, '"City Hall"')
would only return results where the term "City Hall" appears in the Description field, but instead I get results like this:
1 Design of handicap ramp at Manning Hall.
2 Antenna investigation. Client: City of Cranston Engineering Dept.
3 Structural investigation regarding fire damage to International Tennis Hall of Fame.
4 Investigation Roof investigation for proposed satellite design on Herald Hall.
... etc
Obviously those results include at least one of the words in my phrase, but not the phrase itself. What's worse, I had thought the results would be ranked but the two results I actually wanted (because they include the actual phrase) are buried.
SELECT Description
FROM Projects
WHERE Description LIKE '%City Hall%'
1 Major exterior and interior renovation of the existing city hall for Quincy Massachusetts
2 Cursory structural investigation of Pawtucket City Hall tower plagued by leaks.
I'm sure this is a case of me not understanding the documentation, but is there a way to achieve what I'm looking for? Namely, to be able to pass in a search string without quotes and get exactly what I'm getting now or with quotes and get only that exact phrase?
As you said, FREETEXT looks up every word in your phrase, not the phrase as an all. For that you need to use the CONTAINS statement. Like this:
SELECT Description
FROM Projects
WHERE CONTAINS(Description, '"City Hall"')
If you want to get the rank of the results, you have to use CONTAINSTABLE. It works roughly the same, but it returns a table with two columns: [Key] wich contains the primary key of the search table and [Rank], which gives you the rank of the result.
More and more, I'm seeing searches that not only find a substring in a specific column, but they appear to search in all columns. An example is in Amazon, where you can search for "Arnold" and it finds both the movie Running Man starring Arnold Schwarzeneggar, and the Gund toy Arnold the Snoring Pig. I don't know what the term is for this type of search (Wide search? Global search?), and that bugs me. But what I really want to know is what is the normal pattern for accomplishing this type of search in a QUICK way.
The obvious, and slow, way to do it would be to search for the substring "Arnold" in the title, "Arnold" in the author, "Arnold" in the description, etc.
The first quick solution that comes to mind is to store a mapping for each word used to describe a product to the product itself, and then search that word mapping. That could be quick, but doesn't seem very space-efficient to me.
There are probably a hundred ways to accomplish this, some of which probably don't even use a database. But what is the norm?
I've done this in the past by storing an XML version of items in an XML column in the table, then searching in that column instead of the others.
Maybe they're not storing the data the way you expect.
They could, for example, store all titles, authors, descriptions, and every other searchable field in one table with an attribute to distinguish the field's type.
I am trying to determine what the best way is to find variations of a first name in a database. For example, I search for Bill Smith. I would like it return "Bill Smith", obviously, but I would also like it to return "William Smith", or "Billy Smith", or even "Willy Smith". My initial thought was to build a first name hierarchy, but I do not know where I could obtain such data, if it even exists.
Since users can search the directory, I thought this would be a key feature. For example, people I went to school with called me Joe, but I always go by Joseph now. So, I was looking at doing a phonetic search on the last name, either with NYSIIS or Double Metaphone and then searching on the first name using this name heirarchy. Is there a better way to do this - maybe some sort of graded relevance using a full text search on the full name instead of a two part search on the first and last name? Part of me thinks that if I stored a name as a single value instead of multiple values, it might facilitate more search options at the expense of being able to address a user by the first name.
As far as platform, I am using SQL Server 2005 - however, I don't have a problem shifting some of the matching into the code; for example, pre-seeding the phonetic keys for a user, since they wouldn't change.
Any thoughts or guidance would be appreciated. Countless searches have pretty much turned up empty. Thanks!
Edit: It seems that there are two very distinct camps on the functionality and I am definitely sitting in the middle right now. I could see the argument of a full-text search - most likely done with a lack of data normalization, and a multi-part approach that uses different criteria for different parts of the name.
The problem ultimately comes down to user intent. The Bill / William example is a good one, because it shows the mutation of a first name based upon the formality of the usage. I think that building a name hierarchy is the more accurate (and extensible) solution, but is going to be far more complex. The fuzzy search approach is easier to implement at the expense of accuracy. Is this a fair comparison?
Resolution: Upon doing some tests, I have determined to go with an approach where the initial registration will take a full name and I will split it out into multiple fields (forename, surname, middle, suffix, etc.). Since I am sure that it won't be perfect, I will allow the user to edit the "parts", including adding a maiden or alternate name. As far as searching goes, with either solution I am going to need to maintain what variations exists, either in a database table, or as a thesaurus. Neither have an advantage over the other in this case. I think it is going to come down to performance, and I will have to actually run some benchmarks to determine which is best. Thank you, everyone, for your input!
In my opinion you should either do a feature right and make it complete, or you should leave it off to avoid building a half-assed intelligence into a computer program that still gets it wrong most of the time ("Looks like you're writing a letter", anyone?).
In case of human names, a computer will get it wrong most of the time, doing it right and complete is impossible, IMHO. Maybe you can hack something that does the most common English names. But actually, the intelligence to look for both "Bill" and "William" is built into almost any English speaking person - I would leave it to them to connect the dots.
The term you are looking for is Hypocorism:
http://en.wikipedia.org/wiki/Hypocorism
And Wikipedia lists many of them. You could bang out some Python or Perl to scrape that page and put it in a db.
I would go with a structure like this:
create table given_names (
id int primary key,
name text not null unique
);
create table hypocorisms (
id int references given_names(id),
name text not null,
primary key (id, name)
);
insert into given_names values (1, 'William');
insert into hypocorisms values (1, 'Bill');
insert into hypocorisms values (1, 'Billy');
Then you could write a function/sproc to normalize a name:
normalize_given_name('Bill'); --returns William
One issue you will face is that different names can have the same hypocorism (Albert -> Al, Alan -> Al)
I think your basic approach is solid. I don't think fulltext is going to help you. For seeding, behindthename.com seems to have large amount of the data you want.
Are you using SQl Server 2005 Express with Advanced Services as to me it sounds you would benefit from the Full Text indexing and more specifically Contains and Containstable which you can use with specific instructions here is a link for the uses of Containstable:
http://msdn.microsoft.com/en-us/library/ms189760.aspx
and here is the download link for SQL Server 2005 With Advanced Services:
http://www.microsoft.com/downloads/details.aspx?familyid=4C6BA9FD-319A-4887-BC75-3B02B5E48A40&displaylang=en
Hope this helps,
Andrew
You can use the SQL Server Full Text Search and do an inflectional search.
Basically like:
SELECT ProductId, ProductName
FROM ProductModel
WHERE CONTAINS(CatalogDescription, ' FORMSOF(THESAURUS, metal) ')
Check out:
http://en.wikipedia.org/wiki/SQL_Server_Full_Text_Search#Inflectional_Searches
http://msdn.microsoft.com/en-us/library/ms345119.aspx
http://www.mssqltips.com/tip.asp?tip=1491
Not sure what your application is, but if your users know at the time of sign up that people from their past might be searching the database for them, you could offer them the chance in the user profile to define other names they might be known as (including last names, women change these all the time and makes finding them much harder!) and that they want people to be able to search on. Store these in a separate related table. Then search on that. Just make the structure such that you can define one name as the main name (the one you use for everything except the search.)
You'll find that you're dabbling in an area known as "Natural Language Processing" and you'll need to do several things, most of which can be found under the topic of stemming.
Simplistic stemming simply breaks the word apart, but more advanced algorithms associate words that mean the same thing - for instance Google might use stemming to convert "cat" and "kitten" to "feline" and search for all three, weighing the actual word provided by the user as slightly heavier so exact matches return before stemmed matches.
It's a known problem, and there are open source stemmers available.
-Adam
No, Full Text searches will not help to solve your problem.
I think you might want to take a look at some of the following links: (Funny, no one mentioned SoundEx till now)
SoundEx - MSDN
SoundEx - Google results
InformIT - Tolerant Search algorithms
Basically SoundEx allows you to evaluate the level of similarity in similar sounding words. The function is also available on SQL 2005.
As a side issue, instead of returning similar results, it might prove more intuitive to the user to use a AJAX based script to deliver similar sounding names before the user initiates his/her search. That way you can show the user "similar names" or "did you mean..." kind of data.
Here's an idea for automatically finding "name synonyms" like Bill/William. That problem has been studied in the broader context of synonyms in general: inducing them from statistics of which words commonly appear in the same contexts in a large text corpus like the Web. You could try combining that approach with a list of names like Moby Names; I don't know if it's been done before.
Here are some pointers.
I'm looking for a pattern for performing a dynamic search on multiple tables.
I have no control over the legacy (and poorly designed) database table structure.
Consider a scenario similar to a resume search where a user may want to perform a search against any of the data in the resume and get back a list of resumes that match their search criteria. Any field can be searched at anytime and in combination with one or more other fields.
The actual sql query gets created dynamically depending on which fields are searched. Most solutions I've found involve complicated if blocks, but I can't help but think there must be a more elegant solution since this must be a solved problem by now.
Yeah, so I've started down the path of dynamically building the sql in code. Seems godawful. If I really try to support the requested ability to query any combination of any field in any table this is going to be one MASSIVE set of if statements. shiver
I believe I read that COALESCE only works if your data does not contain NULLs. Is that correct? If so, no go, since I have NULL values all over the place.
As far as I understand (and I'm also someone who has written against a horrible legacy database), there is no such thing as dynamic WHERE clauses. It has NOT been solved.
Personally, I prefer to generate my dynamic searches in code. Makes testing convenient. Note, when you create your sql queries in code, don't concatenate in user input. Use your #variables!
The only alternative is to use the COALESCE operator. Let's say you have the following table:
Users
-----------
Name nvarchar(20)
Nickname nvarchar(10)
and you want to search optionally for name or nickname. The following query will do this:
SELECT Name, Nickname
FROM Users
WHERE
Name = COALESCE(#name, Name) AND
Nickname = COALESCE(#nick, Nickname)
If you don't want to search for something, just pass in a null. For example, passing in "brian" for #name and null for #nick results in the following query being evaluated:
SELECT Name, Nickname
FROM Users
WHERE
Name = 'brian' AND
Nickname = Nickname
The coalesce operator turns the null into an identity evaluation, which is always true and doesn't affect the where clause.
Search and normalization can be at odds with each other. So probably first thing would be to get some kind of "view" that shows all the fields that can be searched as a single row with a single key getting you the resume. then you can throw something like Lucene in front of that to give you a full text index of those rows, the way that works is, you ask it for "x" in this view and it returns to you the key. Its a great solution and come recommended by joel himself on the podcast within the first 2 months IIRC.
What you need is something like SphinxSearch (for MySQL) or Apache Lucene.
As you said in your example lets imagine a Resume that will composed of several fields:
List item
Name,
Adreess,
Education (this could be a table on its own) or
Work experience (this could grow to its own table where each row represents a previous job)
So searching for a word in all those fields with WHERE rapidly becomes a very long query with several JOINS.
Instead you could change your framework of reference and think of the Whole resume as what it is a Single Document and you just want to search said document.
This is where tools like Sphinx Search do. They create a FULL TEXT index of your 'document' and then you can query sphinx and it will give you back where in the Database that record was found.
Really good search results.
Don't worry about this tools not being part of your RDBMS it will save you a lot of headaches to use the appropriate model "Documents" vs the incorrect one "TABLES" for this application.