full-text-search

问题 I'm developing a Python tool which uses a sqlite3 virtual table with FTS5 (Full Text Search). I would like to know how to properly install from a tarball (or any other means) the needed requirements for my tool to work so I can pack them for portability. Currently, I managed to install the latest release tarball of sqlite. However, when I execute: python3 -c "import sqlite3; print(sqlite3.sqlite_version)" # or python2 -c "import sqlite3; print(sqlite3.sqlite_version)" I get 3.11.0 , while

问题 I have MySQL on shared hosting. Is there any way how to change value of ft_min_word_len without administrator access? I found one workaround, where every word that has less than 4 characters is supplemented with _ or some other char, and the same is done with every searched keyword that is less than 4 characters. Is there any better, or cleaner way to make Fulltext search work for short words? 回答1: Unfortunately, ft_min_word_len is a global system variable and cannot be set dynamically: see

问题 Does the GAE experimental Full Text Search API provide an alternative to the SQL "LIKE statement"? Thanks! 回答1: No. The SQL like statement supports arbitrary substring matching - for instance, "abbatton" will be a match for "bat" - while fulltext search implements full text indexing, which uses normalization, stemming, and an inverted index to construct an index that is good at answering the sort of queries users tend to enter for textual documents. If you mean "does the Full Text search API

问题 What are the limitations or gotchas or antipatterns or pitfalls? It seems pretty attractive, apparently you can create a search engine with almost no work. But it cannot be without its problems... what are your experiences? 回答1: In my opinion, the greatest drawback is that the MySQL full text indexing is limited to MyISAM tables. As oppsosed to InnoDB tables, those lack a lot of important features, e.g. transactions. 回答2: it cannot be without its problems... It certainly isn't! Any search

问题 Like the title says: can we use ...USING fts3(tokenizer icu th_TH, ...) . If we can, does anyone know what locales are suported, and whether it varies by platform version? 回答1: No, only tokenizer=porter When I specify tokenizer=icu, I get "android.database.sqlite.SQLiteException: unknown tokenizer: icu" Also, this link hints that if Android didn't compile it in by default, it will not be available http://sqlite.phxsoftware.com/forums/t/2349.aspx 回答2: For API Level 21 or up, I tested and found

问题 I have a SQL Server database that I'm searching for keywords. All I need to know is how many of the keywords appear in a column. For example red,green,blue If the column looked like this I like red shoes but not blue It would return the number 2 If the column looked like this I like red shoes and green shoes, but green are my favourite It would also return the number 2 2 of the keywords were found even though one was found twice. Im open to using full text index or anything that is required,

问题 For instance, my query is like the following using SQL Server 2005: SELECT * FROM Table WHERE FREETEXT(SearchField, 'c#') I have a full text index defined to use the column SearchField which returns results when using: SELECT * FROM Table WHERE SearchField LIKE '%c#%' I believe # is a special letter, so how do I allow FREETEXT to work correctly for the query above? 回答1: The # char is indexed as punctuation and therefore ignored, so it looks like we'll remove the letter C from our word

问题 I have a table with a column as nvarchar(max) with text extracted from word documents in it. How can I create a select query that I'll pass another a list of keywords as parameter and return the rows ordered by the number of matches? Maybe it is possible with full text search? 回答1: Yes, possible with full text search, and likely the best answer. For a straight T-SQL solution, you could use a split function and join, e.g. assuming a table of numbers called dbo.Numbers (you may need to decide

问题 I am writing a newsletter script and I need to implement searching in the addresses. I indexed the table with FULLTEXT but when I do a query such as: SELECT * FROM addresses WHERE MATCH(email) AGAINST("name@example.com" IN BOOLEAN MODE) I get strange results. It displays all emails on "example.com" and all emails with user "name". For example I get: john@example.com name@mail.net steven@example.com I rewrote the query to use LIKE "%name@example.com%" but for a big table it takes ridiculous

问题 I am building a custom a find and replace in java. I browse a text file and load the contents in a textarea. Now I have a textBox, where I input a text that needs to be searched. What is the best way to search the text. I know a way using string.indexOf() , but I also need highlighting. So please help me out. 回答1: First of all read Text and New Lines for information on how to get the text to search. Then to highlight the text your find you need to use a Highlighter. The code is something like