How to Copy One MongoDB Database to Another Using mongosh (Without Backup Files)

When working with multiple environments like development and production, it’s common to move data between databases. If both databases are on the same MongoDB server, you can copy all collections and documents directly using mongosh — no backup files required.

In this guide, we’ll copy:

abc-dbname-dev → abc-dbname-prod

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⚠️ Warning Before You Start

This process will:

• Delete existing collections in the target database

• Copy all documents from the source database

• Not copy indexes (data only)

Always take a backup if the target database contains important data.

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Step 1: Open Mongo Shell

mongosh

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Step 2: Run the Copy Script

Paste the following script into the shell:

const sourceDB = "abc-dbname-dev";
const targetDB = "abc-dbname-prod";

db.getSiblingDB(sourceDB).getCollectionNames().forEach(col => {
    const from = db.getSiblingDB(sourceDB)[col];
    const to = db.getSiblingDB(targetDB)[col];

    print(`Copying collection: ${col}`);

    to.drop(); // Remove existing collection
    const docs = from.find().toArray();

    if (docs.length > 0) {
        to.insertMany(docs);
    }
});

print("✅ Copy completed successfully");

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Step 3: Verify the Data

use abc-dbname-prod
show collections

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When Should You Use This Method?

This approach is perfect when:

• Both databases are on the same MongoDB server

• You want a quick clone of dev → prod

• The database size is small to medium

• You don’t need indexes copied

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When NOT to Use This Method

Avoid this method if:

• Your database is very large (use mongodump instead)

• You must preserve indexes

• You want to merge data instead of overwriting

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Bonus: Copy Indexes Too (Optional)

If needed, indexes can also be copied using an extended script.

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Conclusion

Using mongosh to copy databases is a fast and simple solution for environment synchronization during development and testing. For production-scale data migrations, however, prefer mongodump and mongorestore.