This page explores keyspaces and tables in YCQL using the command line shell ycqlsh.

{{% explore-setup-single-new %}}

## YCQL shell

Use the YCQL shell [ycqlsh](../../../api/ycqlsh/) to interact with a Yugabyte database cluster using the [YCQL API](../../../api/ycql/). Because ycqlsh is derived from the Apache Cassandra shell [cqlsh](https://cassandra.apache.org/doc/latest/cassandra/managing/tools/cqlsh.html), most cqlsh commands work as is in ycqlsh.

Using ycqlsh, you can:

- interactively enter YCQL DDL and DML and see the query results
- input from a file or the command line
- use tab completion to automatically complete commands
- use a minimal command name as long as it can be distinguished from other commands (for example, `desc` instead of `DESCRIBE`)

ycqlsh is installed with YugabyteDB and is located in the `bin` directory of the YugabyteDB home directory.

### Connect to a node

From your YugabyteDB home directory, connect to any node of the database cluster as follows:

```sh
$ ./bin/ycqlsh 127.0.0.1
```

This should bring up the following prompt, which prints the version of ycqlsh being used.

```output
Connected to local cluster at 127.0.0.1:9042.
[ycqlsh 5.0.1 | Cassandra 3.9-SNAPSHOT | CQL spec 3.4.2 | Native protocol v4]
Use HELP for help.
ycqlsh>
```

## Users

By default, YugabyteDB has one admin user already created: `cassandra` (the recommended user), and you can check the existing user as follows:

```sql
ycqlsh> select * from system_auth.roles;
```

You should see an output similar to the following:

```output
 role      | can_login | is_superuser | member_of | salted_hash
-----------+-----------+--------------+-----------+------------------------------------------------------------------------------
 cassandra |      True |         True |          [] | $2a$12$64A8Vo0R3K9XeUp26CSzpuWtvUBwOiGFjPAbXGt7wsxZIScGrcsDu\x00\x00\x00\x00
```

## Keyspaces

A keyspace is a container for a set of tables that belong together somehow. If multiple applications are using a
single database, the tables belonging to each application can be grouped into a separate keyspace.
In Apache Cassandra, replication configuration is done at the keyspace level. So, all tables that
require the same replication configuration may be grouped into a keyspace. This pattern does not
apply to YugabyteDB because in YugabyteDB replication configuration is done at the [universe](../../../architecture/key-concepts/#universe) level.

To create a new keyspace `testdb`, run the following statement:

```sql
ycqlsh> CREATE KEYSPACE testdb;
```

To list all keyspaces, use the following command:

```sql
ycqlsh> DESCRIBE KEYSPACES;
```

```output
system_schema  system_auth  testdb  system
```

To use a specific keyspace, use the following command:

```sql
ycqlsh> USE testdb;
```

You should see the following output:

```output
ycqlsh:testdb>
```

To drop the keyspace you just created, use the `DROP` command as follows:

```sql
ycqlsh> DROP KEYSPACE testdb;
```

Verify the keyspace is no longer present as follows:

```sql
ycqlsh> DESCRIBE KEYSPACES;
```

```output
system_schema  system_auth  system
```

## Tables

Create a table using the CREATE TABLE statement.

```sql
CREATE TABLE users (
  id UUID,
  username TEXT,
  enabled boolean,
  PRIMARY KEY (id)
  );
```

To list all tables, use the following command:

```sql
ycqlsh> DESCRIBE TABLES;
```

```output
ycqlsh:testdb> DESCRIBE TABLES;

users
```

To describe the table you created, enter the following:

```sql
ycqlsh> DESCRIBE TABLE users;
```

```output
ycqlsh:testdb> describe table users;

CREATE TABLE testdb.users (
    id uuid PRIMARY KEY,
    username text,
    enabled boolean
) WITH default_time_to_live = 0
    AND transactions = {'enabled': 'false'};
```

{{< note title="Note" >}}
Due to architectural differences, YugabyteDB does _not_ support most of the Apache Cassandra table level properties.
`default_time_to_live` is one of the supported properties and the `transactions` property is added by YugabyteDB. For more details, see [table properties](../../../api/ycql/ddl_create_table/#table-properties-1).
{{< /note >}}
`default_time_to_live` is one of the supported properties. YugabyteDB adds the
`transactions` property. See [table properties](/stable/api/ycql/ddl_create_table/#table-properties-1) for more details.

## Quit ycqlsh

To quit the shell, enter the following command:

```sql
ycqlsh> quit;
```

## Unsupported cqlsh commands

|   Command         |                      Alternative                          |
| :---------------- | :-------------------------------------------------------- |
| LIST ROLES        | select * from system_auth.roles                           |
| SHOW SESSION      | Tracing from ycqlsh is not supported.                   |
| TRACING           | Tracing from ycqlsh is not supported.                   |

## Learn more

- [CREATE KEYSPACE](../../../api/ycql/ddl_create_keyspace)
- [CREATE TABLE](../../../api/ycql/ddl_create_table)