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# MongoDB Full-Text Search Full-text search creates an index for each word, indicating the number of times and the position of the word in the article. When a user queries, the search program searches based on the pre-built index and returns the results to the user. This process is similar to looking up a word in a dictionary using its index. MongoDB has supported full-text search since version 2.4 and currently supports full-text indexes for 15 languages. * danish * dutch * english * finnish * french * german * hungarian * italian * norwegian * portuguese * romanian * russian * spanish * swedish * turkish * * * ## Enabling Full-Text Search MongoDB has full-text search enabled by default since version 2.6. If you are using an earlier version, you need to use the following code to enable full-text search: >db.adminCommand({setParameter:true,textSearchEnabled:true}) Or use the command: mongod --setParameter textSearchEnabled=true * * * ## Creating a Full-Text Index Consider the following document data in the `posts` collection, which contains article content (`post_text`) and tags (`tags`): { "post_text": "enjoy the mongodb articles on Tutorial", "tags": [ "mongodb", "tutorial" ]} We can create a full-text index on the `post_text` field, allowing us to search within the article content: >db.posts.ensureIndex({post_text:"text"}) * * * ## Using the Full-Text Index Now that we have created a full-text index on `post_text`, we can search for the keyword "tutorial" in the articles: >db.posts.find({$text:{$search:"tutorial"}}) The following command returns the document data containing the keyword "tutorial": { "_id" : ObjectId("53493d14d852429c10000002"), "post_text" : "enjoy the mongodb articles on Tutorial", "tags" : [ "mongodb", "tutorial" ]} If you are using an older version of MongoDB, you can use the following command: >db.posts.runCommand("text",{search:"tutorial"}) Using a full-text index can improve search efficiency. * * * ## Deleting a Full-Text Index To delete an existing full-text index, you can use the `find` command to look up the index name: >db.posts.getIndexes() After obtaining the index name with the above command (in this example, the index name is `post_text_text`), execute the following command to delete the index: >db.posts.dropIndex("post_text_text")