DataStax Astra DB includes guardrails and sets limits to ensure good practices, foster availability, and promote optimal configurations for your databases.
Astra DB offers a $25.00 free credit per month, allowing you to create an Astra DB database for free.Create a database with just a few clicks and start developing within minutes.
Each plan includes a $25.00 free credit per month. The $25 credit is good for approximately 30 million reads, 5 million writes, and 40GB of storage per month on a serverless database.
Because Astra DB hides the complexities of database management to help you focus on developing applications, Astra DB is not compatible with DataStax Enterprise (DSE) administrative tools, such as nodetool and dsetool .
Use the DataStax Cloud console to get statistics and view database and health metrics.Astra DB does not support access to the database using the Java Management Extensions (JMX) tools, like JConsole.
Astra DB provides a secure cloud-based database without dramatically changing the way you currently access your internal database:
- New user management flows avoid the need for superusers and global keyspace administration in CQL.
- Endpoints are secured using mutual authentication, either with mutual-TLS or secure tokens issued to the client.
- TLS provides a secure transport layer you can trust, ensuring that in-flight data is protected.
- Data at rest is protected by encrypted volumes.
Additionally, Astra DB incorporates role-based access control (RBAC).
See Security guidelines for more information about how Astra DB implements security.
Replication within regions
Each Astra DB database uses replication across three availability zones within the launched region to promote uptime and ensure data integrity.
The following limits are set for serverless databases created using Astra DB.These limits ensure good practices, foster availability, and promote optimal configurations for your database.
Databases
There is a limit of 5 databases per organization. If you need to increase the number of databases for your organization, https://houston.datastax.com/hc/requests/new[contact DataStax Support, window="_blank"].
Columns
| Parameter | Limit | Notes |
|---|---|---|
| Size of values in a single column | 10 MB | Hard limit. |
| Number of columns per table | 75 | Hard limit. |
Tables
| Parameter | Limit | Notes |
|---|---|---|
| Number of tables per database | 200 | A warning is issued when the database exceeds 100 tables. |
| Table properties | Fixed | All table properties are fixed except for Expiring data with time-to-live. |
Secondary indexes and materialized views are not available for serverless databases. Our team is working to offer materialized views for serverless databases soon.
Workloads
Astra workloads are limited to 4096 ops/sec by default. If you see a "Rate limit reached" error in your application and want your limit raised, please https://houston.datastax.com/hc/requests/new[open a support ticket, window="_blank"].
Storage-Attached Indexing (SAI) limits
The maximum number of SAI indexes on a table is 10. There can be no more than 50 SAI indexes in a single database.
Automated backup and restore
Serverless databases created using Astra DB are automatically backed up once an hour.Snapshots are stored for 20 days, providing a range of options for which you can restore your database, if necessary.
For databases with multiple datacenters in various regions, backup is managed for only the original datacenter selected when creating your database.Restoring from backup removes all other datacenters, restoring to the primary datacenter, and adding the other datacenters with a restored version of the primary datacenter.
If the database was terminated, all data is destroyed and is unrecoverable.
If data is accidentally deleted or corrupted, contact https://houston.datastax.com/hc/requests/new[DataStax Support, window="_blank"] to restore data from one of the available snapshots. This window ensures that the data to restore exists as a saved snapshot.
When restoring data, https://houston.datastax.com/hc/requests/new[DataStax Support, window="_blank"] allows you to restore data on the same cluster if the table is dropped, and data is restored in the same cluster using the specified backup.
The following limits are set for classic databases created using Astra DB.These limits ensure good practices, foster availability, and promote optimal configurations for your database.
Columns
| Parameter | Limit | Notes |
|---|---|---|
| Size of values in a single column | 5 MB | Hard limit. |
| Number of columns per table | 50 | Hard limit. |
Tables
| Parameter | Limit | Notes |
|---|---|---|
| Number of tables per database | 200 | A warning is issued when the database exceeds 100 tables. |
| Table properties | Fixed | All table properties are fixed except for Expiring data with time-to-live. |
| Secondary index | 1 | For classic databases, limit is per table. |
| Materialized view | 2 | Limit is per table. A warning is issued if the materialized view will create large partitions. |
Workloads
Astra DB workloads are limited to 4096 ops/s/coordinator by default. If you see a "Rate limit reached" error in your application and want your limit raised, please https://houston.datastax.com/hc/requests/new[open a support ticket, window="_blank"].
Storage-Attached Indexing (SAI) limits
The maximum number of SAI indexes on a table is 10. There can be no more than 100 SAI indexes in a single database.
Automated backup and restore
Classic databases created using Astra DB are automatically backed up every four hours.The latest six snapshots are stored, providing flexibility in which point in time you can restore to, if necessary.
If the database was terminated, all data is destroyed and is unrecoverable.
If data is accidentally deleted or corrupted, contact DataStax Support within 12 hours to restore data from one of the available snapshots. This window ensures that the data to restore exists as a saved snapshot.
When restoring data, DataStax Support allows you to restore data on the same cluster if the table is dropped, and data is restored in the same cluster using the specified backup.
At this time, user-defined functions (UDFs) and user-defined aggregate functions (UDAs) are not enabled.
| Parameter | Limit | Notes |
|---|---|---|
| Consistency level | Fixed | Supported consistency levels: Reads: Any supported consistency level is permitted Writes: LOCALQUORUM and LOCALSERIAL |
| Compaction strategy | Fixed | UnifiedCompactionStrategy is a more efficient compaction strategy that combines ideas from STCS (SizeTieredCompactionStrategy), LCS (LeveledCompactionStrategy), and TWCS (TimeWindowCompactionStrategy) along with token range sharding. This all-inclusive compaction strategy works well for all use cases. |
| Lists | Fixed | Cannot UPDATE , INSERT , or DELETE a list value by index because Astra DB does not allow list operations which perform a read-before-write. |
| Page size | Fixed | The proper page size is configured automatically. |
| Large partition | Warning | A warning is issued if reading or compacting a partition that exceeds 100 MB. |
CQL commands
The following CQL commands are not supported in Astra DB:
- ALTER KEYSPACE
- ALTER SEARCH INDEX CONFIG
- ALTER KEYSPACE
- ALTER SEARCH INDEX CONFIG
- ALTER SEARCH INDEX SCHEMA
- COMMIT SEARCH INDEX
- CREATE KEYSPACE
- CREATE SEARCH INDEX
- CREATE TRIGGER
- DROP KEYSPACE
- DROP SEARCH INDEX CONFIG
- DROP TRIGGER
- LIST PERMISSIONS
- REBUILD SEARCH INDEX
- RELOAD SEARCH INDEX
- RESTRICT
- RESTRICT ROWS
- UNRESTRICT
- UNRESTRICT ROWS
For supported CQL commands, see the Astra DB CQL quick reference.
cassandra.yaml
If you are an experienced Cassandra or DataStax Enterprise user, you are likely familiar with editing the cassandra.yaml file.For Astra DB, the cassandra.yaml file cannot be configured.
The following limits are included in Astra DB:
- 1