Important
New database features are no longer connected to engine versions; features are now enabled independently during scheduled update windows, and “major” and “minor” releases no longer exist in Helios. Please visit the release notes to view the latest features available in your database clusters.
SHOW DATABASES
On this page
The SHOW DATABASES command shows the list of databases that exist on this SingleStore Helios instance.
Syntax
SHOW DATABASES [EXTENDED]
[LIKE 'pattern']Remarks
-
The
EXTENDEDsuffix is a SingleStore Helios-only extension that displays extra information about each database. -
This command must be run on the master aggregator or a child aggregator node (see Node Requirements for SingleStore Helios Commands).
-
See the Permission Matrix for the required permission.
Output (EXTENDED option)
|
Column |
Description |
|---|---|
|
|
Name of a database in the SingleStore Helios instance |
|
|
Number of committed transactions |
|
|
Database replication role |
|
|
Current state (Database States) |
|
|
Current position in the transaction log in memory, formatted as |
|
|
Optional message about the current state |
|
|
Number of currently attached asynchronous replicas |
|
|
Number of currently attached synchronous replicas |
|
|
Number of currently attached replicas running in consensus mode |
|
|
Position up to which each transaction has been committed |
|
|
Current position in the transaction log on disk |
|
|
Position to which changes have been applied to replica |
|
|
A unique identifier of the current master instance of the database |
|
|
Term of the master that wrote the contents of the most recent page in the log that the secondary instance is aware of the database |
|
|
Memory used by the database |
|
|
Number of transaction log pages (of size 4KB each) that are waiting to be persisted to disk |
Database States
Within a SingleStore Helios instance, users can create one or more databases.
The SHOW DATABASES command with the EXTENDED option adds extra information per-database on top of the standard SHOW DATABASES output.state column conveys the state of each database with respect to replication and recovery.
|
State |
Description |
|---|---|
|
|
The database is available for read and write queries. |
|
|
Not available for read or write queries. |
|
|
Available for read but not write queries. |
|
|
Not available for read or write queries. |
|
|
Not available for read or write queries. |
|
|
Not available for read or write queries. |
|
|
Not available for read or write queries. |
|
|
Databases and partitions are not available for write queries, and are in the process of transitioning to their metadata state. |
Examples
SHOW DATABASES;
+--------------------+
| Database |
+--------------------+
| cluster |
| memsql_demo |
| information_schema |
| memsql |
+--------------------+SHOW DATABASES EXTENDED;
+--------------------+---------+--------+--------+----------+---------+-------------+------------+-----------------+-------------------+------------------+----------------+------+--------------+--------------+-------------+
| Database | Commits | Role | State | Position | Details | AsyncSlaves | SyncSlaves | ConsensusSlaves | CommittedPosition | HardenedPosition | ReplayPosition | Term | LastPageTerm | Memory (MBs) | Pending IOs |
+--------------------+---------+--------+--------+----------+---------+-------------+------------+-----------------+-------------------+------------------+----------------+------+--------------+--------------+-------------+
| cluster | 0 | master | online | 0:130 | | 1 | 0 | 0 | 0:130 | 0:130 | NULL | 24 | 0 | 0.00 | 0 |
| memsql_demo | 0 | master | online | 0:269 | | 1 | 0 | 0 | 0:269 | 0:269 | NULL | 21 | 0 | 0.00 | 0 |
| information_schema | 0 | master | online | 0:1 | | 0 | 0 | 0 | 0:1 | 0:1 | NULL | 2 | 0 | 0.00 | 0 |
| memsql | 0 | master | online | 0:408 | | 0 | 0 | 0 | 0:408 | 0:408 | NULL | 24 | 0 | 0.00 | 0 |
+--------------------+---------+--------+--------+----------+---------+-------------+------------+-----------------+-------------------+------------------+----------------+------+--------------+--------------+-------------+Last modified: