mongodb delete all documents in every collection

mongosh 'mongodb+srv://YOUR_MONGODB_ATLAS_URL.mongodb.net/' --apiVersion 1 --username YOUR_ADMIN_USERNAME

> Enter password:
(enter password)

use my-database-name

db.getCollectionNames().forEach((collection_name) => {
  if (collection_name.indexOf("system.") > -1) {
    return;
  }
  print("\n----------------------------------------");
  print(["COLLECTION:", collection_name].join('\n'));
  print(
    ["    Removing ", db[collection_name].count({}), " documents …"].join("")
  );
  db[collection_name].remove({});
  print(["    Count: ", db[collection_name].count({}), " documents"].join(""));
  print("----------------------------------------\n");
});

exit

cvan/mongodb_delete_all_collections_documents.md