# System Limits

This topic specifies maximum sizes and numbers of various SingleStore Helios components. Use the following links to navigate to a section below:

## Workspace-Level Limits

| Components                                                                  | Limit                                                                                                                                                                                                                                                                                                                                                              |
| --------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ |
| Maximumworkspaces in a group                                                | 5                                                                                                                                                                                                                                                                                                                                                                  |
| Maximum number ofworkspaces to which a database can be attached in R/W mode | 1                                                                                                                                                                                                                                                                                                                                                                  |
| Maximumworkspacesize                                                        | S-384 (vCPU: 3072; Memory: 24576 GB)Refer to the[pricing](https://www.singlestore.com/cloud-pricing/#compute)page for more details.                                                                                                                                                                                                                                |
| Number of databases perworkspace                                            | No fixed limit. It depends on the size of each database. Databases are sized differently based on the number of partitions, amount of data, metadata and number of tables, etc.Refer to[SingleStore Helios Sizing Guidelines](https://docs.singlestore.com/cloud/getting-started-with-singlestore-helios/singlestore-helios-sizing-guidelines.md)for more details. |
| Maximum number of concurrent queries                                        | This varies according to the deployment size.                                                                                                                                                                                                                                                                                                                      |
| Maximum simultaneous client connections                                     | This varies according to the deployment size.                                                                                                                                                                                                                                                                                                                      |

## Database-Level Limits

| Item                                   | Max Spec (enforced) | Max Spec (recommended) | Comments                                         |
| -------------------------------------- | ------------------- | ---------------------- | ------------------------------------------------ |
| Number of tables in a database         |                     |                        | Each table costs some per-table memory overhead. |
| Number of partitions in aworkspace     | None                |                        |                                                  |
| Number of database partitions per node | 2414                |                        |                                                  |

## Table-Level Limits

| Item                                                                 | Max Spec (enforced) | Max Spec (recommended) | Comments                                                                               |
| -------------------------------------------------------------------- | ------------------- | ---------------------- | -------------------------------------------------------------------------------------- |
| Number of columns per table                                          | 4096                |                        |                                                                                        |
| Row size in bytes                                                    | 64KB \*             |                        | Limit does not apply to variable-length strings such as VARCHAR, VARBINARY, TEXT, etc. |
| Length of names in characters (applies to table names, column names) | 256                 |                        |                                                                                        |
| Number of indexes per table                                          | 63                  |                        |                                                                                        |
| Number of columns per index                                          | 32                  |                        |                                                                                        |
| Number of tables in a join for each SELECT                           | 253                 |                        |                                                                                        |
| Number of entries in a`SELECT`projection (target) list               | 12800               |                        |                                                                                        |
| Number of nested sub-select queries using the`UNION`statement        | 337                 | 40                     | Beyond 40 the`UNION`statements are converted to`TABLE`function.                        |

\* The number of fields that will fit in the 64KB maximum row size is determined by the field types and how rows are laid out in the in-memory rowstore format. In some cases, writes (inserts and updates) to columnstore tables are implemented by storing the newly written rows in a rowstore format before flushing them to the column-oriented format. The row size limit applies to fixed-width data which includes a 4-byte nullability flag for nullable fields. The row size limit does not include the body of variable-width fields, but only the in-row portion, which includes an 8-byte memory location pointer and an optional 4-byte nullability flag. The sum of the in-row data size for all columns cannot exceed 64KB."

## Naming Constraints

| Item                                                                                                                                    | Constraints                                                                                                                                                                                   |
| --------------------------------------------------------------------------------------------------------------------------------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| General                                                                                                                                 | <ul> <li>Name cannot be blank.</li> <li>Name cannot end with a space.</li> </ul>                                                                                                              |
| Database names                                                                                                                          | <ul> <li>Database names can only contain alphanumeric characters and underscores, and cannot start with a digit.</li> <li>Maximum length of 64 characters.</li> </ul>                         |
| Table names                                                                                                                             | <ul> <li>Table names can contain both alphanumeric and non-alphanumeric characters, but cannot contain the <code>/</code> character.</li> <li>Maximum length of 256 characters. **</li> </ul> |
| Other database objects (stored procedures, views, user-defined functions, user-defined aggregate functions, and table-valued functions) | Maximum length of 256 characters. \*\*                                                                                                                                                        |
| User names                                                                                                                              | <ul> <li>Non-JWT users: Maximum length of 32 characters.</li> <li>JWT users: Maximum length of 320 characters.</li> </ul>                                                                     |
| Role names                                                                                                                              | No length limit. Cannot contain commas or spaces.                                                                                                                                             |
| Group names                                                                                                                             | No length limit. Cannot contain commas or spaces.                                                                                                                                             |

\*\* Column aliases are truncated during projection (`SELECT`) to 256 bytes (not characters) which impacts names that use multi-byte characters. The full names are stored in the database and can be queried. Information schema tables can be used to view the full names.

***

Modified at: August 25, 2025

Source: [/cloud/reference/configuration-reference/system-limits/](https://docs.singlestore.com/cloud/reference/configuration-reference/system-limits/)

(An index of the documentation is available at /llms.txt)