Resharding and consolidating databases
InfinigraphNot available on AuraIntroduced in 2025.12

Neo4j supports several methods for resharding a database, depending on your specific requirements and constraints:

  • Server resharding (online): Selecting more property shards than needed at creation time to allow space for their data to grow or by adjusting the number of property shard replicas to allow for more or less redundancy and read scalability.

  • Database resharding: Copying an existing standard database, or starting with Neo4j 2026.03, a backup of an existing standard or sharded property database, to create a new sharded property database with the desired number of property shards.

Server resharding (online)

There are two ways to reshard a sharded property database online:

Select more property shards than needed at creation time (online)

You can select more property shards than needed at creation time and allow space for their data to grow, as the Neo4j cluster allows databases to be moved based on server availability. For example, six property shards can be initially hosted across three servers (two shards per server), with additional servers added as needed.

Creating a sharded property database with more property shards than needed at creation time
CREATE DATABASE foo
GRAPH SHARD     { TOPOLOGY 1 PRIMARY 0 SECONDARIES }
PROPERTY SHARDS { COUNT 6 TOPOLOGY 1 REPLICA };

For details on managing databases and servers in a cluster, see Managing databases in a cluster and Managing servers in a cluster.

Scale by adjusting the number of property shard replicas (online)

You can adjust the number of property shard replicas in a sharded property database to allow for more or less redundancy and read scalability without downtime.

For example, to change the number of replicas for the property shard foo-sharded-p000, connect to the DBMS either via the driver or Cypher Shell, and run the following command:

ALTER DATABASE `foo-sharded-p000`
SET TOPOLOGY 2 REPLICAS;

Database resharding

You can create a new sharded property database with the desired number of property shards by copying an existing database, which can be a standard database, or starting with Neo4j 2026.03, a backup of an existing standard or sharded property database.

Split an existing database into shards (offline)

You can use the neo4j-admin database copy command to create a sharded property database from a standard database, specifying the number of property shards for the new database. The existing database must be stopped during the copying process.

The following options can be specified for the neo4j-admin database copy command:

  • --copy-schema — (optional) to copy the schema of the existing database if needed.

  • --property-shard-count — the number of property shards to create for the new database, which must be more than 0.

  • --target-location — a path to a folder for target backup artifact data. Used together with --target-format=backup.

  • --target-format — the format of the output data. Possible values are backup and database (default).

  • --compress — Introduced in 2026.04 (optional) produces compressed backup artifacts. See Copy a database store for more information.

It is not possible to specify a store format for sharded databases; if specified, it will be ignored, and a warning will be logged.

The following example shows how to create a new sharded property database, called foo-sharded, in a cluster deployment, from the existing standard database foo. The foo database must be stopped during the copying process.

  1. Copy the data from the existing database foo into the database foo-sharded, creating one graph shard and three property shards:

    neo4j-admin database copy foo foo-sharded --copy-schema --property-shard-count 3 --target-location=s3://bucket/folder/ --target-format=backup

    For more information about the syntax and options of the neo4j-admin database copy command, see Copy a database store.

    Copying a database does not automatically create it. Therefore, it will not be visible if you do SHOW DATABASES at this point.

  2. Connect to the DBMS either via the driver or Cypher Shell, and run the following command to create the database foo-sharded, as a sharded property database by seeding it from your backup folder in the AWS S3 bucket:

    CREATE DATABASE `foo-sharded`
DEFAULT LANGUAGE CYPHER 25
PROPERTY SHARDS { COUNT 3 }
OPTIONS {seedUri: “s3://bucket/folder/”};

    The cluster automatically distributes the data across its servers. For other seed data options, see Creating a sharded database from a URI (online).

  3. Verify that the new database is online by running the following command:

    SHOW DATABASES;

Create a sharded property database from a backup of a standard database (online)
Introduced in 2026.03

You can use the neo4j-admin database copy command to create a sharded property database from a backup of a standard database. The process is similar to resharding a database by splitting an existing database into shards, but instead of using a standard database as the source, you use a backup of a standard database.

The following options can be specified for the neo4j-admin database copy command:

  • --source-location — a path to the full backup of an existing database or the last diff backup in the chain. This folder can be located locally or remotely (e.g., an S3 bucket) and must contain the full backup and all the diff backups in the chain, if any.

  • --source-format=backup — the format of the source backup.

  • --copy-schema — (optional) to copy the schema of the existing database if needed.

  • --property-shard-count — the number of property shards to create for the new database, which must be more than 0.

  • --target-location — a path to a folder for target backup artifact data. Used together with --target-format=backup.

  • --target-format — the format of the output data. Possible values are backup and database (default).

  • --compress — Introduced in 2026.04 (optional) produces compressed backup artifacts. See Copy a database store for more information.

--source-location and --source-format cannot be used together with --from-path-data and/or --from-path-txn due to the conflict in trying to supply data from two different locations at once.
It is also not possible to specify a store format for sharded databases; if specified, it will be ignored, and a warning will be logged.

The following example shows how to create a sharded property database, called foo-sharded, with 3 property shards, from a backup of the existing database foo, in a cluster deployment. It assumes that you have a backup of your existing database foo in an AWS S3 bucket. If you do not have a backup of your database or you are unsure whether you have a current backup, follow steps 1 and 2. Otherwise, proceed directly to step 3.

  1. Connect to the DBMS either via the driver or Cypher Shell, and put the database foo into read-only mode to ensure your sharded version of foo will have all the data after copying as the old database.

    ALTER DATABASE foo SET ACCESS READ ONLY;

  2. Back up the database foo to a location that is accessible by the cluster, such as an AWS S3 bucket, using the neo4j-admin database backup command. The --type=full option forces the creation of a full backup of the database even if there are existing full backups in the specified location.

    bin/neo4j-admin database backup --type=full --to-path=s3://bucket/folder/ foo

    For more information about the syntax and options of the neo4j-admin database backup command, see Back up a database to a cloud storage.

  3. Copy the data from a backup of your standard database foo into the database foo-sharded, creating one graph shard and three property shards.

    neo4j-admin database copy foo foo-sharded --source-location=s3://bucket/folder/foo.backup --source-format=backup --copy-schema --property-shard-count 3 --target-location=s3://bucket/folder --target-format=backup

    For more information about the syntax and options of the neo4j-admin database copy command, see Copy a database store.

    Copying a database does not automatically create it. Therefore, it will not be visible if you do SHOW DATABASES at this point.

  4. Connect to the DBMS either via the driver or Cypher Shell, and run the following command to create the database foo-sharded as a sharded property database by seeding it from your backup folder in the AWS S3 bucket:

    CREATE DATABASE `foo-sharded`
DEFAULT LANGUAGE CYPHER 25
PROPERTY SHARDS { COUNT 3 }
OPTIONS {seedUri: “s3://bucket/folder/”};

    The cluster automatically distributes the data across its servers. For other seed data options, see Create a database from a URI.

  5. Wait until the last committed transaction ID is the same for all allocations of the database and then verify that the new database is online by running the following command:

    SHOW DATABASES;

  6. After the new database is online, you can drop the old database foo if it is no longer needed, or put it into read-write mode if you want to keep it for other purposes.

    Run the following command to drop the old database foo:

    DROP DATABASE foo;

    Change the access mode of the old database foo to read-write:

    ALTER DATABASE foo SET ACCESS READ WRITE;

Create a sharded property database from a backup of a sharded property database (online)
Introduced in 2026.03

You can use the neo4j-admin database copy command to create a new sharded property database from a backup of an existing sharded property database and specify a different number of property shards for the new database. The process is similar to creating a sharded property database from a backup of a standard database, but instead of using a backup file as the source, you specify the folder containing all backups of an existing sharded property database as the source.

Keep in mind that this process can take a long time to complete, especially if the existing database is large, as it involves copying all data from all the shards and redistributing it across the new shards.

The following options can be specified for the neo4j-admin database copy command:

  • --source-location — a path to a folder containing all backups of an existing sharded property database, including the full backup and all the diff backups in the chain of the graph shard and the last full backup for each property shard. This folder can be located locally or remotely (e.g., an S3 bucket).

  • --source-format=backup — the format of the source backup.

  • --copy-schema — (optional) to copy the schema of the existing database if needed.

  • --property-shard-count — the number of property shards to create for the new database, which must be more than 0.

  • --target-location — a path to a folder for target backup artifact data. Used together with --target-format=backup.

  • --target-format — the format of the output data. Possible values are backup and database (default).

  • --compress — Introduced in 2026.04 (optional) produces compressed backup artifacts. See Copy a database store for more information.

  • The name of the database to copy from must be the name of the virtual database.

--source-location and --source-format cannot be used together with --from-path-data and/or --from-path-txn due to the conflict in trying to supply data from two different locations at once.
It is also not possible to specify a store format for sharded databases; if specified, it will be ignored, and a warning will be logged.

The following example shows how to create a sharded property database, called foo-sharded-new, with 5 property shards, from a backup of the existing sharded property database, foo-sharded, in a cluster deployment. It assumes that you have a backup of your existing sharded property database foo-sharded in an AWS S3 bucket.
If you do not have a backup of your database or you are unsure whether you have a current backup, see Backup and restore for instructions on how to back up your database. To be completely sure that all backups are on the same transaction, it is recommended to put the database into read-only mode, running ALTER DATABASE foo-sharded SET ACCESS READ ONLY using Cypher Shell or the driver. Copy works even if the backups of the shards have different last applied transactions but there might be some data loss due to one shard not having all information from the last transactions.

  1. Copy the data from a backup of your sharded property database foo-sharded into the database foo-sharded-new, changing the number of property shards to 5:

    neo4j-admin database copy foo-sharded foo-sharded-new --source-location=s3://bucket/folder --source-format=backup --copy-schema --property-shard-count 5 --target-location=s3://bucket/folder/ --target-format=backup

    For more information about the syntax and options of the neo4j-admin database copy command, see Copy a database store.

    Copying a database does not automatically create it. Therefore, it will not be visible if you do SHOW DATABASES at this point.

  2. Connect to the DBMS either via the driver or Cypher Shell, and run the following command to create the database foo-sharded-new as a sharded property database by seeding it from your backup folder in the AWS S3 bucket:

    CREATE DATABASE `foo-sharded-new`
DEFAULT LANGUAGE CYPHER 25
PROPERTY SHARDS { COUNT 5 }
OPTIONS {seedUri: “s3://bucket/folder/”};

    The cluster automatically distributes the data across its servers. For other seed data options, see Create a database from a URI.

  3. Wait until the last committed transaction ID is the same for all allocations of the database and then verify that the new database is online by running the following command:

    SHOW DATABASES;

  4. After the new database is online, you can drop the old database foo-sharded if it is no longer needed, or put it into read-write mode if you want to keep it for other purposes.

    Run the following command to drop the old database foo-sharded:

    DROP DATABASE foo-sharded;

    Change the access mode of the old database foo-sharded to read-write:

    ALTER DATABASE foo-sharded SET ACCESS READ WRITE;

Database consolidation

You can consolidate a sharded property database into a standard database by copying the data from the sharded property database into a new standard database, or by creating a new standard database from a backup of the sharded property database.

Consolidating a sharded property database into a standard database

To consolidate a sharded property database into a standard database, you can use the neo4j-admin database copy command to create a new standard database from an existing sharded property database. The existing sharded property database must be stopped during the copying process.

The following options can be specified for the neo4j-admin database copy command:

  • --copy-schema — (optional) to copy the schema of the existing database if needed.

  • --target-location — a path to a folder for target backup artifact data. Used together with --target-format=backup.

  • --target-format — the format of the output data. Possible values are backup and database (default).

  • --to-format=block — the store format of the output data, which must be block for standard databases.

  • --compress — Introduced in 2026.04 (optional) produces compressed backup artifacts. See Copy a database store for more information.

The following example shows how to create a new standard database, called foo, in a cluster deployment, from the existing sharded property database foo-sharded. The foo-sharded database must be stopped during the copying process.

  1. Copy the data from the existing database foo-sharded into the database foo, creating a standard database with no property shards:

    neo4j-admin database copy foo-sharded foo --copy-schema --to-format=block --target-location=s3://bucket/folder/ --target-format=backup

    For more information about the syntax and options of the neo4j-admin database copy command, see Copy a database store.

    Copying a database does not automatically create it. Therefore, it will not be visible if you do SHOW DATABASES at this point.

  2. Connect to the DBMS either via the driver or Cypher Shell, and run the following command to create the database foo, as a standard database by seeding it from your backup folder in the AWS S3 bucket:

    CREATE DATABASE `foo`
DEFAULT LANGUAGE CYPHER 25
OPTIONS {seedUri: “s3://bucket/folder/”};

    The cluster automatically distributes the data across its servers. For other seed data options, see Creating a sharded database from a URI (online).

  3. Verify that the new database is online by running the following command:

    SHOW DATABASES;

  4. After the new database is online, you can drop the database foo-sharded if it is no longer needed:

    DROP DATABASE foo-sharded;

Consolidating a sharded property database into a standard database by using a backup of the sharded property database

To consolidate a sharded property database into a standard database, you can use the neo4j-admin database copy command to create a new standard database from a backup of an existing sharded property database. The process is similar to creating a standard database from a sharded property database, but instead of using a sharded property database as the source, you use a backup of an existing sharded property database as the source.

The following options can be specified for the neo4j-admin database copy command:

  • --source-location — a path to a folder containing all backups of an existing sharded property database, including the full backup and all the diff backups in the chain of the graph shard and the last full backup for each property shard. This folder can be located locally or remotely (e.g., an S3 bucket).

  • --source-format=backup — the format of the source backup.

  • --copy-schema — (optional) to copy the schema of the existing database if needed.

  • --target-location — a path to a folder for target backup artifact data. Used together with --target-format=backup.

  • --target-format — the format of the output data. Possible values are backup and database (default).

  • --to-format=block — the store format of the output data, which must be block for standard databases.

  • --compress — Introduced in 2026.04 (optional) produces compressed backup artifacts. See Copy a database store for more information.

  • The name of the database to copy from must be the name of the virtual database.

--source-location and --source-format cannot be used together with --from-path-data and/or --from-path-txn due to the conflict in trying to supply data from two different locations at once.

The following example shows how to create a standard database, called foo from a backup of the existing sharded property database, foo-sharded, in a cluster deployment. It assumes that you have a backup of your existing sharded property database foo-sharded in an AWS S3 bucket.
If you do not have a backup of your database or you are unsure whether you have a current backup, see Backup and restore for instructions on how to back up your database. To be completely sure that all backups are on the same transaction, it is recommended to put the database into read-only mode, running ALTER DATABASE foo-sharded SET ACCESS READ ONLY using Cypher Shell or the driver. Copy works even if the backups of the shards have different last applied transactions but there might be some data loss due to one shard not having all information from the last transactions.

  1. Copy the data from a backup of your sharded property database foo-sharded into a standard database foo:

    neo4j-admin database copy foo-sharded foo --to-format=block --source-location=s3://bucket/folder --source-format=backup --copy-schema --target-location=s3://bucket/folder/ --target-format=backup

    For more information about the syntax and options of the neo4j-admin database copy command, see Copy a database store.

    Copying a database does not automatically create it. Therefore, it will not be visible if you do SHOW DATABASES at this point.

  2. Connect to the DBMS either via the driver or Cypher Shell, and run the following command to create the database foo as a standard database by seeding it from your backup folder in the AWS S3 bucket:

    CREATE DATABASE `foo`
DEFAULT LANGUAGE CYPHER 25
OPTIONS {seedUri: “s3://bucket/folder/”};

    The cluster automatically distributes the data across its servers. For other seed data options, see Create a database from a URI.

  3. Verify that the new database is online by running the following command:

    SHOW DATABASES;

Glossary

allocator

A component in the cluster that allocates databases to servers according to the topology constraints specified and an allocation strategy.

asynchronous replication

Asynchronous replication is used by secondary copies to poll for new transactions, which means they cannot be guaranteed to have received the most recent transactions. This enables efficient scale-out of read-performance.

Aura instance

A fully-managed DBMS represented by a single instance ID, that is running in the Neo4j Aura cloud.

auto-commit transaction

An automatically committed transaction that contains a single query.

Bolt protocol

Bolt is a protocol used for interaction between Neo4j instances and drivers.

bookmark

A marker the client can request from the cluster to ensure that it is able to read its own writes so that the application’s state is consistent and only databases that have a copy of the bookmark are permitted to respond.

category (Bloom)

A category is based on a node label and is defined in a Perspective as a way of visually distinguishing nodes with the same label(s).

causal consistency

All servers in a cluster agree on the order in which transactions take place. The position of a server on the causal chain can be guaranteed using a bookmark.

cluster

A Neo4j DBMS that spans multiple servers working together to increase fault tolerance and/or read scalability. Databases on a cluster may be configured to replicate across servers in the cluster thus achieving read scalability or high availability.

client application

Software that interacts with a Neo4j server.

commit

A commit is the successful completion of a transaction, which ensures durability of any changes made. For more details, visit Operations Manual → Transaction management.

composite database

Composite databases are the means to access partitioned graph data with a single Cypher query.

constraint

Constraints are sets of data modeling rules that ensure the data is consistent and reliable.

Cypher®

Neo4j’s graph query language.

data model

A data model defines how information is organized in a database. A good data model will make querying and understanding your data easier. In Neo4j, the data models have a graph structure.

database

A database is a container used by the DBMS to manage and store graph data. The physical structure of data is controlled by the database.

database vs graph

Databases are the physical containers of graph data. Graphs are the logical structure of data in Neo4j.

Database Management System

Database Management System, or DBMS, capable of managing multiple databases. A DBMS may run on a single server, or span several servers configured as a cluster.

database schema

The prescribed property existence and datatypes for nodes and relationships.

deallocate

An act of removing a database from a server or a server from a cluster without loss of data or reduced fault tolerance.

degree (of a node)

The number of relationships of a specific node; loops are counted twice.

disaster recovery

A manual intervention to restore availability of a cluster, or databases within a cluster.

driver

A software library that provides access to Neo4j from a particular programming language.

election

In the event that the Raft leader becomes unresponsive, followers automatically trigger an election and vote for a new leader.

entity

A node or a relationship.

expression (Cypher)

A component of a Cypher query which produces values. It may be used in projections, as a predicate, or when setting properties on graph elements.

fabric

Fabric is the architectural design of a unified system that provides a single access point to local or distributed graph data.

fault tolerance

A guarantee that a cluster can maintain a database’s persistence and availability in the event of one or more servers failing.

follower

A primary copy of a database acting as a follower, receives and acknowledges synchronous writes from the leader.

Generative AI (GenAI)

A type of artificial intelligence (AI) system that generates text, images, or other media in response to prompts.

graph

A logical representation of a set of nodes where some pairs are connected by relationships.

index

Data structure that improves read performance of a database.

knowledge graph

A specific type of graph that has an organizing principle so that a user (or a computer system) can reason about the underlying data. The organizing principle provides an additional layer of structure that adds context to support knowledge discovery.

label

Marks a node as a member of a named and indexed subset. A node may be assigned zero or more labels.

leader

A single primary copy of a database is designated as the leader. It receives all write transactions from clients and replicates writes synchronously to followers and asynchronously to secondary copies of the database.

main database

In terms of Neo4j Enterprise Studio, the database(s) containing the user’s data. Can exist in the same Neo4j deployment as the tool asset database.

motif

A description of a specific pattern within a graph.

node

A node represents an entity or discrete object in your graph data model. Nodes can be connected by relationships, hold data in properties, and are classified by labels.

operator

A symbol representing a mathematical or logical operation.

parameter

Named value provided when running a Cypher statement.

path

A sequence of nodes and the relationships connecting them, that does not contain duplicate relationships. Several paths can match a pattern.

pattern

A specific arrangement of nodes and relationships that can be matched in a graph. A pattern follows a motif.

perspective (Bloom)

A Perspective defines a certain business view or domain that can be found in the target Neo4j graph. A single Neo4j graph can be viewed through different Perspectives, each tailored for a different business purpose.

primary

A copy of the database that is able to process write transactions and is eligible to be elected as a leader. It participates in fault tolerant writes as it is part of the majority required to acknowledge and commit write transactions.

primary vs secondary

In a cluster, databases can operate in either primary or secondary mode. Primary databases are able to process write and read transactions, ensuring fault tolerance. Secondary databases are replicated asynchronously from primaries, and their main purpose is to provide read scaling within the cluster.

project (Aura)

An isolated environment in the unified Aura console that contains its own database instances, configurations, and resources. Preceded by tenant in the classic Aura console.

property

Properties are key-value pairs that are used for storing data on nodes and relationships.

query (Cypher)

A statement that retrieves or writes information to a database.

Raft group

A group of servers that are participating in hosting a particular database in primary mode.

Raft group member

A server that is participating in a Raft group. A server can be a member of one or more groups.

Raft log

A shared log between all Raft group members that is guaranteed to be consistently updated and viewed by those members. The log contains both database data and operational state of the Raft group.

Raft protocol

The networking mechanism that enables a database to replicate its data across multiple servers to give high availability for accessing the data and high durability to the data stored.

read scaling

Distributing query load by creating additional database copies hosted in secondary mode (read-only).

relationship

A relationship represents a connection between nodes in your graph data model. Relationships connect a source node to a target node, hold data in properties, and are classified by type.

secondary

An asynchronously replicated copy of the database that provides read scaling within the cluster.

seed

A seed is a database dump or a full backup used to create a database on a cluster. This is sometimes called seeding.

server

A physical machine, a virtual machine, or a container running an instance of Neo4j. Servers can be standalone or part of a cluster.

session

A causally linked sequence of transactions.

session consistency

An alternative name for Neo4j’s causal consistency.

standalone

A single server running Neo4j and not part of a cluster.

synchronous replication

Synchronous replication requires the leader primary to replicate a transaction and block the commit until a quorum of the follower primaries acknowledges that the transaction is successfully replicated. Once the transaction is replicated, the commit is allowed to proceed. This ensures data durability and consistency within the cluster.

system database

A database used by Neo4j to store system information.

tenant (Aura)

An isolated environment in the classic Aura console that contains its own database instances, configurations, and resources. Replaced by project in the unified Aura console.

tool asset database

In terms of Neo4j Enterprise Studio, the database where tools' assets are stored. This can be in the same Neo4j deployment as the main database(s) or in a separate deployment.

topology

A configuration that describes how the copies of a database should be spread across the servers in a cluster, see primary mode and secondary mode.

transaction

A transaction comprises a unit of work performed against a database. It is treated in a coherent and reliable way, independent of other transactions. Transactions comply with the ACID consistency model (atomic, consistent, isolated, and durable).