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# Conflicts:
#	README.md

doc/persistent-mongodb.md

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+# MongoDB FlexSearch
+
+MongoDB is a common NoSQL document store providing everything you might want from a solid FlexSearch storage solution.
+
+You'll need to install the npm package `mongodb` into your project:
+```bash
+npm install mongodb@6.13.0
+```
+
+Create an index and assign a MongoDB storage adapter to it by using `index.mount(db)`:
+
+```js
+import Index from "./index.js";
+import Database from "./db/mongodb/index.js";
+// create an index
+const index = new Index();
+// create db instance with optional namespace
+const db = new Database("my-store");
+// mount and await before transfering data
+await index.mount(db);
+
+// update the index as usual
+index.add(1, "content...");
+index.update(2, "content...");
+index.remove(3);
+
+// changes are automatically committed by default
+// when you need to wait for the task completion, then you
+// can use the commit method explicitely:
+await index.commit();
+```
+
+> Changes are automatically committed by default when you need to wait for the task completion, then you can use the `await index.commit()` method explicitely. You can disable the auto-commit feature optionally.
+
+## Configuration
+
+### Custom DB Instance
+
+Pass a valid `mongodb` instance on creation:
+
+```js
+import { MongoClient } from "mongodb";
+import Database from "./db/mongodb/index.js";
+// assume you've created a custom database instance...
+const database = new MongoClient("mongodb://localhost:27017/");
+// connect and await
+await database.connect();
+// pass database instance as option
+const db = new Database("my-store", {
+    db: database
+});
+```
+
+For every instance of `DocumentIndex`, `WorkerIndex` or `Index` (as standalone) you'll need to create a `Database` instance having its own name.
+
+### Table Structure
+
+FlexSearch is creating different `DATABASE` entries for each index name e.g. "my-store". That is how you can use different stores for different indexes at the same time without getting collision of naming inheritance. Document Indexes will map their field names into table names respectively.
+
+```
+DATABASE
+   |__COLLECTION map:field (FlexSearch Data) 
+   |__COLLECTION ctx:field (FlexSearch Data) 
+   |__COLLECTION tag:field (FlexSearch Data) 
+   |__COLLECTION cfg:field (FlexSearch Data) 
+   |__COLLECTION reg       (FlexSearch Data) 
+```