When you create a wildcard index in MongoDB, you have the option of specifying a single field, all fields, or just some.
You can use the wildcardProjection parameter to include or exclude specific field paths from the wildcard index. This article presents an example of including specific fields in the wildcard index.
When you create a text index in MongoDB, the index uses a default language of english.
The default language determines the rules to parse word roots (i.e. stemming) and ignore stop words.
However, you can change the default language if required.
You can also specify a language at the document level, and even at the subdocument level. The default language will only be used if a language hasn’t been specified at the document or subdocument level.
This article presents examples of specifying a language for a text index.
There are various types of indexes that you can create in MongoDB. If you have a field that contains a string or an array of strings, you can use a text index on that field.
When you create a text index in MongoDB, you have the option of applying different weights to each indexed field.
These weights denote the relative significance of the indexed fields to each other. A field with a higher weight will have more impact in the search results than a field with a lower weight.
This provides you with a certain amount of control over how the search results are calculated.
The default weight is 1, so if you don’t specify a weight for field, it will be assigned a weight of 1.
Continue readingMongoDB provides us with the ability to create wildcard text indexes.
Wildcard text indexes are similar to wildcard indexes, except that wildcard text indexes support the $text operator, whereas wildcard indexes don’t.
That said, creating each index type is very similar in the sense that they both share the wildcard $** field pattern.
In MongoDB, you can use the getIndexes() method to get a list of indexes on a collection.
You can also loop through each collection in a database to return all indexes in the database.
Continue readingIn MongoDB, you can create an index on a collection using the createIndex() method, the createIndexes() method, or the createIndexes administration command.
There are several ways to create an index in MongoDB, and from MongoDB 4.2, we can create wildcard indexes.
A wildcard index can be thought of as a kind of filter that automatically matches any field, sub-document or array in a collection and then indexes those matches.
Continue readingIn MongoDB, the setFeatureCompatibilityVersion command enables or disables the features that persist data incompatible with earlier versions of MongoDB.
The example on this page demonstrates how to view the featureCompatibilityVersion for a mongod instance.