Changing ClickHouse® settings at the query level
- Getting the list of ClickHouse® settings at the query level
- Specifying ClickHouse® settings using the Yandex Cloud interfaces
- Specifying ClickHouse® settings in a user account
- Specifying ClickHouse® settings in the settings profile
- Specifying ClickHouse® settings in a session
- Specifying ClickHouse® settings when connecting to a database via the command line
You can specify ClickHouse® settings at the query level
-
Using the Yandex Cloud interfaces. This way, you can specify only the ClickHouse® settings available in Yandex Cloud.
-
Using SQL queries. This way you can specify any ClickHouse® settings at the query level. The method of specifying settings depends on their type:
-
User settings. In the
CREATE USER
andALTER USER
SQL queries, you can use theSETTINGS
condition to provide settings. This way, settings will apply to the selected user only.To use this method, enable the User management via SQL option when creating or updating the cluster. After that, you will not be able to manage users using the Yandex Cloud interfaces; however, you cannot disable user management via SQL.
-
Settings at the profile level. In ClickHouse®, the settings profile
contains the values and limitations of these settings as well as the list of roles and users to whom the profile applies. ClickHouse® settings are provided in theCREATE SETTINGS PROFILE
andALTER SETTINGS PROFILE
SQL queries.To use this method, enable the User management via SQL option when creating or updating the cluster.
-
Session settings. During a session, you can provide ClickHouse® settings using the
SET
SQL query. This way you can specify settings in a cluster with any configuration, but they will apply to the current session only.This method is not suitable for all SQL editors: in some of them, every query runs in a separate session. Check the characteristics of your SQL editor before configuring a session.
-
Connection settings. When you connect to a database using the clickhouse-client utility, you can specify ClickHouse® settings using flags. This way you can specify settings in a cluster with any configuration, but they will apply to the currently established connection only.
You can also specify connection settings in different drivers for ClickHouse® or provide them as URL parameters when sending ClickHouse® HTTP API requests. For more information about these methods, see the ClickHouse® documentation
.
-
Getting the list of ClickHouse® settings at the query level
-
Connect to the database in the cluster.
-
Run the following query:
SELECT name, description, value FROM system.settings;
The result contains names, descriptions, and values of ClickHouse® settings at the query level. The result displays values for the current session and the user who established that session.
Specifying ClickHouse® settings using the Yandex Cloud interfaces
To configure ClickHouse®:
- In the management console
, go to the folder page and select Managed Service for ClickHouse. - Click the name of the cluster you need, then go the Users section.
- In the appropriate user row, click
and select Settings. - In the Advanced settings list, expand settings and specify the ClickHouse® settings.
- Click Save changes.
If you do not have the Yandex Cloud command line interface yet, install and initialize it.
The folder specified in the CLI profile is used by default. You can specify a different folder using the --folder-name
or --folder-id
parameter.
To configure ClickHouse®:
-
View the full list of settings specified for a user:
yc managed-clickhouse user get <username> <cluster_name_or_ID>
-
View the description of the CLI command for changing user settings:
yc managed-clickhouse user update --help
-
Set the required parameter values:
yc managed-clickhouse user update <username> <cluster_name_or_ID> \ --settings="<parameter_1_name>=<value_1>,<parameter_2_name>=<value_2>,..."
To configure ClickHouse®:
-
Open the current Terraform configuration file with an infrastructure plan.
For more information about creating this file, see Creating clusters.
-
In the Managed Service for ClickHouse® cluster user description, under
settings
, change the values of the following parameters:resource "yandex_mdb_clickhouse_cluster" "<cluster_name>" { ... user { name = <username> ... settings { <parameter1_name> = <value1> <parameter2_name> = <value2> ... } } ... }
-
Make sure the settings are correct.
-
Using the command line, navigate to the folder that contains the up-to-date Terraform configuration files with an infrastructure plan.
-
Run the command:
terraform validate
If there are errors in the configuration files, Terraform will point to them.
-
-
Confirm updating the resources.
-
Run the command to view planned changes:
terraform plan
If the resource configuration descriptions are correct, the terminal will display a list of the resources to modify and their parameters. This is a test step. No resources are updated.
-
If you are happy with the planned changes, apply them:
-
Run the command:
terraform apply
-
Confirm the update of resources.
-
Wait for the operation to complete.
-
-
For more information, see the Terraform provider documentation
Time limits
A Terraform provider sets the timeout for Managed Service for ClickHouse® cluster operations:
- Creating a cluster, including by restoring one from a backup: 60 minutes.
- Editing a cluster: 90 minutes.
- Deleting a cluster: 30 minutes.
Operations exceeding the set timeout are interrupted.
How do I change these limits?
Add the timeouts
block to the cluster description, for example:
resource "yandex_mdb_clickhouse_cluster" "<cluster_name>" {
...
timeouts {
create = "1h30m" # 1 hour 30 minutes
update = "2h" # 2 hours
delete = "30m" # 30 minutes
}
}
-
Get an IAM token for API authentication and place it in the environment variable:
export IAM_TOKEN="<IAM_token>"
-
Use the User.update method and make a request, e.g., using cURL
:Warning
This API method overrides all parameters of the object being modified that were not explicitly passed in the request to the default values. To avoid this, list the settings you want to change in the
updateMask
parameter (one line separated by commas).curl \ --request PATCH \ --header "Authorization: Bearer $IAM_TOKEN" \ --header "Content-Type: application/json" \ --url 'https://mdb.api.cloud.yandex.net/managed-clickhouse/v1/clusters/<cluster_ID>/users/<username>' \ --data '{ "updateMask": "<list_of_settings_to_update>", "settings": { <ClickHouse®_settings> } }'
Where:
-
updateMask
: List of parameters to update as a single string, separated by commas. -
settings
: Required ClickHouse® settings with new values.
You can get the cluster ID with a list of clusters in the folder. You can request the user name with the list of users in the cluster.
-
-
View the server response to make sure the request was successful.
-
Get an IAM token for API authentication and place it in the environment variable:
export IAM_TOKEN="<IAM_token>"
-
Clone the cloudapi
repository:cd ~/ && git clone --depth=1 https://github.com/yandex-cloud/cloudapi
Below, we assume the repository contents are stored in the
~/cloudapi/
directory. -
Use the UserService/Update call and make a request, e.g., using gRPCurl
:Warning
This API method will assign default values to all object parameters not explicitly set in the request. To avoid this, list the settings you want to change in the
update_mask
parameter as an array ofpaths[]
strings.Format for listing settings
"update_mask": { "paths": [ "<setting_1>", "<setting_2>", ... "<setting_N>" ] }
grpcurl \ -format json \ -import-path ~/cloudapi/ \ -import-path ~/cloudapi/third_party/googleapis/ \ -proto ~/cloudapi/yandex/cloud/mdb/clickhouse/v1/user_service.proto \ -rpc-header "Authorization: Bearer $IAM_TOKEN" \ -d '{ "cluster_id": "<cluster_ID>", "user_name": "<username>", "update_mask": { "paths": [ <list_of_settings_to_update> ] }, "settings": { <ClickHouse®_settings> } }' \ mdb.api.cloud.yandex.net:443 \ yandex.cloud.mdb.clickhouse.v1.UserService.Update
Where:
-
update_mask
: List of parameters to update as an array ofpaths[]
strings. -
settings
: Required ClickHouse® settings with new values.
You can get the cluster ID with a list of clusters in the folder. You can request the user name with the list of users in the cluster.
-
-
View the server response to make sure the request was successful.
Specifying ClickHouse® settings in a user account
You can specify ClickHouse® settings when adding a new user or changing settings of an existing user.
Adding a new user with ClickHouse® settings
-
Connect to the DB in the cluster using the
admin
account. -
Create a user:
CREATE USER <username> IDENTIFIED WITH sha256_password BY '<user_password>' SETTINGS <list_of_ClickHouse®_settings>;
Note
The username may contain Latin letters, numbers, hyphens, and underscores but must begin with a letter or underscore.
The password must be from 8 to 128 characters long.
In the
SETTINGS
parameter, apart from with the setting value, you can specify its minimum and maximum value. Here is an example for the idle_connection_timeout setting:CREATE USER <username> IDENTIFIED WITH sha256_password BY 'password' SETTINGS idle_connection_timeout = 60 MIN 5 MAX 120;
For more information about creating users, see the ClickHouse® documentation
.
Changing ClickHouse® settings of a user
-
Connect to the DB in the cluster using the
admin
account. -
Update the user account.
ALTER USER <username> SETTINGS <list_of_ClickHouse®_settings>;
For more information on updating accounts, see the ClickHouse® documentation
.
Specifying ClickHouse® settings in the settings profile
You can specify ClickHouse® settings when creating or updating a settings profile.
Creating a profile with ClickHouse® settings
-
Connect to the DB in the cluster using the
admin
account. -
Create a settings profile:
CREATE SETTINGS PROFILE <settings_profile_name> SETTINGS <list_of_ClickHouse®_settings>;
In the
SETTINGS
parameter, apart from with the setting value, you can specify its minimum and maximum value. Here is an example for the idle_connection_timeout setting:CREATE SETTINGS PROFILE <settings_profile_name> SETTINGS idle_connection_timeout = 60 MIN 5 MAX 120;
You can attach a settings profile to a user:
CREATE SETTINGS PROFILE <settings_profile_name> SETTINGS <list_of_ClickHouse®_settings> TO <username>;
For more information about creating settings profiles, see the ClickHouse® documentation
.
Changing ClickHouse® settings in the settings profile
-
Connect to the DB in the cluster using the
admin
account. -
Update a settings profile:
ALTER SETTINGS PROFILE <settings_profile_name> SETTINGS <list_of_ClickHouse®_settings>;
In this query, you can specify the boundary values of settings and bind the profile to a user. For more information about changing settings profiles, see the ClickHouse® documentation
.
Specifying ClickHouse® settings in a session
-
Connect to the database in the cluster.
-
Run the following query:
SET <username> SETTINGS <list_of_ClickHouse®_settings>;
The applied settings will be valid during the opened session only.
-
Make sure the settings were applied:
SELECT value FROM system.settings;
To view the value of a setting, run this query:
SELECT value FROM system.settings WHERE name='<setting_name>';
Specifying ClickHouse® settings when connecting to a database via the command line
-
Set the dependencies required for connecting to a database.
-
View the description of the command for connecting to a database:
clickhouse-client --help
Most flags in the command output are advanced ClickHouse® settings.
-
Select the flags with the required settings by matching the flag names with the names of ClickHouse® settings
. -
Specify the selected flags in the command for connecting to a database:
-
Connecting without SSL:
clickhouse-client --host <FQDN_of_any_ClickHouse®_host> \ --user <username> \ --database <db_name> \ --port 9000 \ --ask-password \ <flags_with_ClickHouse®_settings>
-
Connecting via SSL:
clickhouse-client --host <FQDN_of_any_ClickHouse®_host> \ --secure \ --user <username> \ --database <db_name> \ --port 9440 \ --ask-password \ <flags_with_ClickHouse®_settings>
-
Here is an example of connecting without SSL with the idle_connection_timeout
setting:clickhouse-client --host rc1d-***.mdb.yandexcloud.net \ --user user1 \ --database db1 \ --port 9440 \ --ask-password \ --idle_connection_timeout 60
-
-
Make sure the settings were applied:
SELECT value FROM system.settings;
To view the value of a setting, run this query:
SELECT value FROM system.settings WHERE name='<setting_name>';
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