Migrate a database
Not available on Aura

You can use the neo4j-admin database migrate command to migrate a Neo4j database from one store format to another or to a later MAJOR version of the same format.

A store format defines how the data of a database is stored on the file system.

The store format of a database is versioned with the MAJOR.MINOR scheme, independent of the Neo4j calendar versioning. An upgrade to the latest MINOR format version is an automatic operation performed on database startup. A migration to a higher MAJOR format version or another format is a manual action performed with the migrate command.

The store format for new databases can be set with the db.format configuration setting.

The table below shows supported migration paths between different Neo4j store formats. However, the standard and high_limit store formats are deprecated starting with Neo4j 5.23, meaning that migration to these formats is not recommended from this version onward.

Table 1. Migration paths between Neo4j store formats
Store format	Migration paths
Store format	To `block`	To `aligned`	To `high_limit`	To `standard`
`block` ^[1]		Not recommended	Not recommended
`aligned` ^[2]			Not recommended
`high_limit` ^[3]
`standard` ^[4]			Not recommended
1. The `block` format is the default in Enterprise Edition starting from Neo4j 5.22. 2. The `aligned` format is the default in Community Edition. In Enterprise Edition, it was default before Neo4j 5.22. 3. Enterprise Edition The `high_limit` format is deprecated in 5.23. 4. Community Edition The `standard` format is deprecated in 5.23.

Before migrating from block to the aligned format, you have to ensure that your graph fits in the aligned since the block format has higher limits. For details, see Database internals and transactional behavior → Store formats.

Syntax

The neo4j-admin database migrate has the following syntax:

neo4j-admin database migrate [-h] [--expand-commands]
                             [--force-btree-indexes-to-range]
                             [--verbose] [--additional-config=<file>]
                             [--max-off-heap-memory=<size>] [--pagecache=<size>]
                             [--to-format=standard|high_limit|aligned|block] <database>

The neo4j-admin database migrate command is run only on a stopped database.

Parameters

Table 2. `neo4j-admin database migrate` parameters
Parameter	Description
`<database>`	Name of the database to migrate. Can contain * and ? for globbing. Note that * and ? have special meaning in some shells and might need to be escaped or used with quotes.

Options

The neo4j-admin database migrate command has the following options:

Option Description Default

--additional-config=<file>^[5]

Configuration file with additional configuration.

--expand-commands

Allow command expansion in config value evaluation.

--force-btree-indexes-to-range

Special option for automatically turning all BTREE indexes/constraints into RANGE. Be aware that RANGE indexes are not always the optimal replacement of BTREEs and performance may be affected while the new indexes are populated. See the Neo4j v5 migration guide online for more information. The newly created indexes will be populated in the background on the first database start up following the migration and users should monitor the successful completion of that process.

This option is only relevant when migrating from Neo4j 4.4.

-h, --help

Show this help message and exit.

--max-off-heap-memory=<size> Introduced in Neo4j 2025.04

Maximum off-heap memory that the command can use for page cache and various caching data structures to improve performance. Use this option to tune the command memory usage; the command does not use the server.memory.pagecache.size configuration setting for this purpose. Values can be plain numbers, such as 10000000, or, for example, 20G for 20 gigabytes, or 70%, which will amount to 70% of currently free memory on the machine.

90%

--pagecache=<size> Deprecated in Neo4j 2025.04

The size of the page cache to use for the migration process. The general rule is that values up to the size of the database proportionally increase performance.

--to-format=standard|high_limit|aligned|block

Name of the format to migrate the store to. If the format is specified, the target database is migrated to the latest known combination of MAJOR and MINOR versions of the specified format. If not specified, the tool migrates the target database to the latest known combination of MAJOR and MINOR versions of the current format.

--verbose

Enable verbose output.

5. See Neo4j Admin and Neo4j CLI → Configuration for details.

The block format is the default format for all databases in Enterprise Edition as long as they do not have the db.format setting specified. For more information on the block format, see Store formats.

Example

The following example migrates the movies database to the latest known combination of MAJOR and MINOR versions of the block format:

bin/neo4j-admin database migrate --to-format=block movies

Example output

2025-01-22 18:03:21.842+0000 INFO  [c.n.c.d.EnterpriseMigrateStoreCommand] Starting migration for database 'movies'
2025-01-22 18:03:22.504+0000 INFO  [o.n.k.i.s.StoreMigrator] 'record-aligned-1.1' has been identified as the current version of the store
2025-01-22 18:03:22.504+0000 INFO  [o.n.k.i.s.StoreMigrator] 'block-block-1.1' has been identified as the target version of the store migration
2025-01-22 18:03:22.506+0000 INFO  [o.n.k.i.s.StoreMigrator] Starting migration of database
2025-01-22 18:03:22.586+0000 INFO  [o.n.k.i.s.StoreMigrator] Migrating Store files (1/1):
2025-01-22 18:03:22.588+0000 INFO  [o.n.k.i.s.StoreMigrator] Store files
2025-01-22 18:03:23.270+0000 INFO  [c.n.i.b.i.BlockBatchImporter] Import completed successfully, took 654ms.
2025-01-22 18:03:23.708+0000 INFO  [o.n.k.i.s.StoreMigrator]  10% completed
2025-01-22 18:03:23.708+0000 INFO  [o.n.k.i.s.StoreMigrator]  20% completed
2025-01-22 18:03:23.708+0000 INFO  [o.n.k.i.s.StoreMigrator]  30% completed
2025-01-22 18:03:23.708+0000 INFO  [o.n.k.i.s.StoreMigrator]  40% completed
2025-01-22 18:03:23.709+0000 INFO  [o.n.k.i.s.StoreMigrator]  50% completed
2025-01-22 18:03:23.709+0000 INFO  [o.n.k.i.s.StoreMigrator]  60% completed
2025-01-22 18:03:23.709+0000 INFO  [o.n.k.i.s.StoreMigrator]  70% completed
2025-01-22 18:03:23.709+0000 INFO  [o.n.k.i.s.StoreMigrator]  80% completed
2025-01-22 18:03:23.709+0000 INFO  [o.n.k.i.s.StoreMigrator]  90% completed
2025-01-22 18:03:23.709+0000 INFO  [o.n.k.i.s.StoreMigrator] 100% completed
2025-01-22 18:03:23.761+0000 INFO  [o.n.k.i.s.StoreMigrator] Starting transaction logs migration.
2025-01-22 18:03:23.800+0000 INFO  [o.n.k.i.s.StoreMigrator] Transaction logs migration completed.
2025-01-22 18:03:23.802+0000 INFO  [o.n.k.i.s.StoreMigrator] Successfully finished migration of database, took 1s 296ms
2025-01-22 18:03:23.804+0000 INFO  [c.n.c.d.EnterpriseMigrateStoreCommand] Database migration completed successfully

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).

Migrate a databaseNot available on Aura