driver-core/src/main/com/mongodb/client/model/changestream/ChangeStreamDocument.java
@BsonIgnore @Nullable
    public String getDatabaseName() {
        if (namespaceDocument == null) {
            return null;
        }
        if (!namespaceDocument.containsKey("db")) {
            return null;
        }
        return namespaceDocument.getString("db").getValue();
    }
@BsonIgnore @Nullable
    public String getDatabaseName() {
        if (namespaceDocument == null) {
            return null;
        }
        if (!namespaceDocument.containsKey("db")) {
            return null;
        }
        return namespaceDocument.getString("db").getValue();
    }
Returns the database name

@return the databaseName. If the namespaceDocument is null or if it is missing the 'db' key, then this will
return null.
@since 3.8