How to search text in MongoDB

MongoDB allows you search for a word in the database

db.articles.find( { $text: { $search: "coffee" } } )

There doesn't seem to be an equivalent in matlab's interface to MongoDB.

Any thoughts on how to search for a string in the database?

Answer 1

[Nipun Katyal]

Make sure you have a proper installation of MongoDB and the corresponding support packages in matlab

To connect to an existing database here is the link to the documentation

https://www.mathworks.com/help/database/ug/database-toolbox-interface-for-mongodb-installation.html

https://www.mathworks.com/help/database/ug/mongo.html

To connect to an existing database

server = "dbtb01";
port = 27017;
dbname = "mongotest";
conn = mongo(server,port,dbname)

To execute a search query

collection = "employee";
mongoquery = '{"department":"Sales"}';
documents = find(conn,collection,'Query',mongoquery);

[Thomas Dufresne]

I already have everything working like this example. My question is "Is there a way to do a search text string for a partial match (e.g. find the word "dog" in a field of a collection)?". The example you show just returns exact matches for a string. MongoDB manual shows the text parameter being used. For example:

_db.articles.find( { $text: { $search: "coffee" } } )

to find all strings containing the word 'coffee'. The text delimeter doesn't appear to be in the matlab find command. Any help would be appreciated -Thanks

[Nipun Katyal]

One way is to extract a collection from the database which is stored as a structure.

collection = "articles";
documents = find(conn,collection);

To search for a string in a structure we can use structfun as given in the link

https://www.mathworks.com/matlabcentral/answers/331786-how-to-search-a-field-in-a-structure-and-extract-all-fields-that-match

[Thomas Dufresne]

Thanks for your response. I was hoping to find a way that can actually search the database first for the occurrence of a text string, as opposed to pulling everything into matlab and then searching for a text string within a structure. It appears that MongoDB can search for a string within the database, but that not feature is not available in the matlab implementation.

[Ralf Elsas]

Hi, I was just bothering with the same problem.

A solution I have found is to use the $regex command in the find function:

mongoquery = '{"label": {$regex: "pay"}}'

finds all documents where the text variable "label" contains "pay", using find(conn,collection,'Query',mongoquery).

Hope this helps.