Optimize remove

Author: alisnic

lib/mongo/Mutator.js

@@ -343,8 +343,14 @@ export default class Mutator {
       delete removeOptions.projection;
     }
 
-    // TODO: optimization check if it has _id or _id with {$in} so we don't have to redo this.
-    const docs = await this.find(selector, removeOptions).fetchAsync();
+    let docs
+
+    if (Object.keys(selector).length === 1 && typeof selector._id === "string") {
+      docs = [{ _id: selector._id }];
+    } else {
+      docs = await this.find(selector, removeOptions).fetchAsync();
+    }
+
     let docIds = docs.map((doc) => doc._id);
 
     if (!selector._id) {