ClickHouse

Use ClickHouse to query and insert analytical data, manage databases and tables, inspect schemas and system state, and execute SQL.

The block uses ClickHouse’s HTTP interface. The endpoint must be reachable from the Sim execution runtime and allowed by its network policy.

Connection details

• Host — your ClickHouse hostname (e.g. your-instance.clickhouse.cloud or your server address).
• Port — the HTTP interface port. Use 8443 for HTTPS (ClickHouse Cloud) or 8123 for plain HTTP (self-hosted).
• Database / Username — default to default if not specified.
• Password — optional for unauthenticated local instances.
• Use HTTPS — keep enabled for any remote or Cloud instance.

Mutations and network access

• UPDATE and DELETE are implemented as ClickHouse mutations (ALTER TABLE ... UPDATE/DELETE). Mutations run asynchronously in the background, so the affected row count is not returned immediately.
• ClickHouse is optimized for bulk inserts. Prefer batching many rows per insert over many single-row inserts.
• Private and internal hosts are blocked by default. Self-hosted operators can configure an explicit database egress allowlist; a host must also be reachable from the runtime.

Use the block

Query and insert data, manage databases and tables, inspect schemas, monitor mutations and running queries, manage partitions, and execute raw SQL over the ClickHouse HTTP interface.

Actions

ClickHouse Query

Execute a SELECT query on a ClickHouse database

Inputs and outputs

Input

Parameter	Type	Required	Description
host	string	Yes	ClickHouse server hostname (e.g., your-instance.clickhouse.cloud)
port	number	Yes	ClickHouse HTTP interface port (8443 for HTTPS, 8123 for HTTP)
database	string	Yes	Database name to connect to
username	string	Yes	ClickHouse username
password	string	No	ClickHouse password
secure	boolean	No	Use a secure HTTPS connection (default: true)
query	string	Yes	SQL SELECT query to execute

Output

Parameter	Type	Description
message	string	Operation status message
rows	array	Array of rows returned from the query
rowCount	number	Number of rows returned

ClickHouse Execute

Execute raw SQL (DDL, mutations, or queries) on a ClickHouse database

Inputs and outputs

Input

Parameter	Type	Required	Description
host	string	Yes	ClickHouse server hostname (e.g., your-instance.clickhouse.cloud)
port	number	Yes	ClickHouse HTTP interface port (8443 for HTTPS, 8123 for HTTP)
database	string	Yes	Database name to connect to
username	string	Yes	ClickHouse username
password	string	No	ClickHouse password
secure	boolean	No	Use a secure HTTPS connection (default: true)
query	string	Yes	Raw SQL statement to execute

Output

Parameter	Type	Description
message	string	Operation status message
rows	array	Array of rows returned from the statement
rowCount	number	Number of rows returned or affected

ClickHouse Insert

Insert a row into a ClickHouse table

Inputs and outputs

Input

Parameter	Type	Required	Description
host	string	Yes	ClickHouse server hostname (e.g., your-instance.clickhouse.cloud)
port	number	Yes	ClickHouse HTTP interface port (8443 for HTTPS, 8123 for HTTP)
database	string	Yes	Database name to connect to
username	string	Yes	ClickHouse username
password	string	No	ClickHouse password
secure	boolean	No	Use a secure HTTPS connection (default: true)
table	string	Yes	Table name to insert data into
data	object	Yes	Data object to insert (key-value pairs mapping column names to values)

Output

Parameter	Type	Description
message	string	Operation status message
rows	array	Inserted rows (empty for ClickHouse inserts)
rowCount	number	Number of rows inserted

ClickHouse Insert Rows

Insert multiple rows into a ClickHouse table

Inputs and outputs

Input

Parameter	Type	Required	Description
host	string	Yes	ClickHouse server hostname (e.g., your-instance.clickhouse.cloud)
port	number	Yes	ClickHouse HTTP interface port (8443 for HTTPS, 8123 for HTTP)
database	string	Yes	Database name to connect to
username	string	Yes	ClickHouse username
password	string	No	ClickHouse password
secure	boolean	No	Use a secure HTTPS connection (default: true)
table	string	Yes	Table to insert into
rows	json	Yes	Array of row objects to insert, e.g. [{"id":1,"name":"a"},{"id":2,"name":"b"}]

Output

Parameter	Type	Description
message	string	Operation status message
rows	array	Inserted rows (empty for ClickHouse inserts)
rowCount	number	Number of rows inserted

ClickHouse Update

Update rows in a ClickHouse table via an ALTER TABLE ... UPDATE mutation

Inputs and outputs

Input

Parameter	Type	Required	Description
host	string	Yes	ClickHouse server hostname (e.g., your-instance.clickhouse.cloud)
port	number	Yes	ClickHouse HTTP interface port (8443 for HTTPS, 8123 for HTTP)
database	string	Yes	Database name to connect to
username	string	Yes	ClickHouse username
password	string	No	ClickHouse password
secure	boolean	No	Use a secure HTTPS connection (default: true)
table	string	Yes	Table name to update data in
data	object	Yes	Data object with fields to update (key-value pairs)
where	string	Yes	WHERE clause condition (without the WHERE keyword)

Output

Parameter	Type	Description
message	string	Operation status message
rows	array	Updated rows (empty for ClickHouse mutations)
rowCount	number	Number of rows written by the mutation

ClickHouse Delete

Delete rows from a ClickHouse table via an ALTER TABLE ... DELETE mutation

Inputs and outputs

Input

Parameter	Type	Required	Description
host	string	Yes	ClickHouse server hostname (e.g., your-instance.clickhouse.cloud)
port	number	Yes	ClickHouse HTTP interface port (8443 for HTTPS, 8123 for HTTP)
database	string	Yes	Database name to connect to
username	string	Yes	ClickHouse username
password	string	No	ClickHouse password
secure	boolean	No	Use a secure HTTPS connection (default: true)
table	string	Yes	Table name to delete data from
where	string	Yes	WHERE clause condition (without the WHERE keyword)

Output

Parameter	Type	Description
message	string	Operation status message
rows	array	Deleted rows (empty for ClickHouse mutations)
rowCount	number	Number of rows affected by the mutation

ClickHouse List Databases

List all databases on a ClickHouse server

Inputs and outputs

Input

Parameter	Type	Required	Description
host	string	Yes	ClickHouse server hostname (e.g., your-instance.clickhouse.cloud)
port	number	Yes	ClickHouse HTTP interface port (8443 for HTTPS, 8123 for HTTP)
database	string	Yes	Database name to connect to
username	string	Yes	ClickHouse username
password	string	No	ClickHouse password
secure	boolean	No	Use a secure HTTPS connection (default: true)

Output

Parameter	Type	Description
message	string	Operation status message
rows	array	List of databases with engine and comment
rowCount	number	Number of rows returned

ClickHouse List Tables

List tables in the connected ClickHouse database

Inputs and outputs

Input

Parameter	Type	Required	Description
host	string	Yes	ClickHouse server hostname (e.g., your-instance.clickhouse.cloud)
port	number	Yes	ClickHouse HTTP interface port (8443 for HTTPS, 8123 for HTTP)
database	string	Yes	Database name to connect to
username	string	Yes	ClickHouse username
password	string	No	ClickHouse password
secure	boolean	No	Use a secure HTTPS connection (default: true)

Output

Parameter	Type	Description
message	string	Operation status message
rows	array	Array of rows returned from the query
rowCount	number	Number of rows returned

ClickHouse Describe Table

Describe the columns of a ClickHouse table

Inputs and outputs

Input

Parameter	Type	Required	Description
host	string	Yes	ClickHouse server hostname (e.g., your-instance.clickhouse.cloud)
port	number	Yes	ClickHouse HTTP interface port (8443 for HTTPS, 8123 for HTTP)
database	string	Yes	Database name to connect to
username	string	Yes	ClickHouse username
password	string	No	ClickHouse password
secure	boolean	No	Use a secure HTTPS connection (default: true)
table	string	Yes	Table name to describe

Output

Parameter	Type	Description
message	string	Operation status message
rows	array	Array of rows returned from the query
rowCount	number	Number of rows returned

ClickHouse Show Create Table

Get the CREATE TABLE statement (DDL) for a ClickHouse table

Inputs and outputs

Input

Parameter	Type	Required	Description
host	string	Yes	ClickHouse server hostname (e.g., your-instance.clickhouse.cloud)
port	number	Yes	ClickHouse HTTP interface port (8443 for HTTPS, 8123 for HTTP)
database	string	Yes	Database name to connect to
username	string	Yes	ClickHouse username
password	string	No	ClickHouse password
secure	boolean	No	Use a secure HTTPS connection (default: true)
table	string	Yes	Table name to get the CREATE statement for

Output

Parameter	Type	Description
message	string	Operation status message
ddl	string	The CREATE TABLE statement

ClickHouse Count Rows

Count rows in a ClickHouse table, optionally filtered

Inputs and outputs

Input

Parameter	Type	Required	Description
host	string	Yes	ClickHouse server hostname (e.g., your-instance.clickhouse.cloud)
port	number	Yes	ClickHouse HTTP interface port (8443 for HTTPS, 8123 for HTTP)
database	string	Yes	Database name to connect to
username	string	Yes	ClickHouse username
password	string	No	ClickHouse password
secure	boolean	No	Use a secure HTTPS connection (default: true)
table	string	Yes	Table name to count rows in
where	string	No	Optional WHERE clause condition without the WHERE keyword

Output

Parameter	Type	Description
message	string	Operation status message
count	number	Number of rows

ClickHouse Introspect

Introspect a ClickHouse database to retrieve table structures, columns, and engines

Inputs and outputs

Input

Parameter	Type	Required	Description
host	string	Yes	ClickHouse server hostname (e.g., your-instance.clickhouse.cloud)
port	number	Yes	ClickHouse HTTP interface port (8443 for HTTPS, 8123 for HTTP)
database	string	Yes	Database name to introspect
username	string	Yes	ClickHouse username
password	string	No	ClickHouse password
secure	boolean	No	Use a secure HTTPS connection (default: true)

Output

Parameter	Type	Description
message	string	Operation status message
tables	array	Array of table schemas with columns and engines
↳ name	string	Table name
↳ database	string	Database the table belongs to
↳ engine	string	Table engine (e.g., MergeTree, Log)
↳ totalRows	number	Approximate total number of rows in the table
↳ columns	array	Table columns
↳ name	string	Column name
↳ type	string	ClickHouse data type (e.g., UInt32, String, DateTime)
↳ defaultKind	string	Kind of default expression (DEFAULT, MATERIALIZED, ALIAS)
↳ defaultExpression	string	Default value expression for the column
↳ isInPrimaryKey	boolean	Whether the column is part of the primary key
↳ isInSortingKey	boolean	Whether the column is part of the sorting key

ClickHouse Create Database

Create a new database on a ClickHouse server

Inputs and outputs

Input

Parameter	Type	Required	Description
host	string	Yes	ClickHouse server hostname (e.g., your-instance.clickhouse.cloud)
port	number	Yes	ClickHouse HTTP interface port (8443 for HTTPS, 8123 for HTTP)
database	string	Yes	Database name to connect to
username	string	Yes	ClickHouse username
password	string	No	ClickHouse password
secure	boolean	No	Use a secure HTTPS connection (default: true)
name	string	Yes	Name of the database to create

Output

Parameter	Type	Description
message	string	Operation status message

ClickHouse Drop Database

Drop a database from a ClickHouse server

Inputs and outputs

Input

Parameter	Type	Required	Description
host	string	Yes	ClickHouse server hostname (e.g., your-instance.clickhouse.cloud)
port	number	Yes	ClickHouse HTTP interface port (8443 for HTTPS, 8123 for HTTP)
database	string	Yes	Database name to connect to
username	string	Yes	ClickHouse username
password	string	No	ClickHouse password
secure	boolean	No	Use a secure HTTPS connection (default: true)
name	string	Yes	Name of the database to drop

Output

Parameter	Type	Description
message	string	Operation status message

ClickHouse Create Table

Create a new MergeTree-family table in ClickHouse

Inputs and outputs

Input

Parameter	Type	Required	Description
host	string	Yes	ClickHouse server hostname (e.g., your-instance.clickhouse.cloud)
port	number	Yes	ClickHouse HTTP interface port (8443 for HTTPS, 8123 for HTTP)
database	string	Yes	Database name to connect to
username	string	Yes	ClickHouse username
password	string	No	ClickHouse password
secure	boolean	No	Use a secure HTTPS connection (default: true)
table	string	Yes	Name of the table to create
columns	json	Yes	Array of column definitions, each an object with name and type, e.g. [{"name":"id","type":"UInt64"},{"name":"ts","type":"DateTime"}]
engine	string	No	Table engine (default MergeTree)
orderBy	string	Yes	ORDER BY expression, e.g. "id" or "(id, ts)"
partitionBy	string	No	Optional PARTITION BY expression, e.g. toYYYYMM(ts)

Output

Parameter	Type	Description
message	string	Operation status message

ClickHouse Drop Table

Drop a table from a ClickHouse database

Inputs and outputs

Input

Parameter	Type	Required	Description
host	string	Yes	ClickHouse server hostname (e.g., your-instance.clickhouse.cloud)
port	number	Yes	ClickHouse HTTP interface port (8443 for HTTPS, 8123 for HTTP)
database	string	Yes	Database name to connect to
username	string	Yes	ClickHouse username
password	string	No	ClickHouse password
secure	boolean	No	Use a secure HTTPS connection (default: true)
table	string	Yes	Table name to drop

Output

Parameter	Type	Description
message	string	Operation status message

ClickHouse Truncate Table

Remove all rows from a ClickHouse table

Inputs and outputs

Input

Parameter	Type	Required	Description
host	string	Yes	ClickHouse server hostname (e.g., your-instance.clickhouse.cloud)
port	number	Yes	ClickHouse HTTP interface port (8443 for HTTPS, 8123 for HTTP)
database	string	Yes	Database name to connect to
username	string	Yes	ClickHouse username
password	string	No	ClickHouse password
secure	boolean	No	Use a secure HTTPS connection (default: true)
table	string	Yes	Table name to truncate

Output

Parameter	Type	Description
message	string	Operation status message

ClickHouse Rename Table

Rename a ClickHouse table

Inputs and outputs

Input

Parameter	Type	Required	Description
host	string	Yes	ClickHouse server hostname (e.g., your-instance.clickhouse.cloud)
port	number	Yes	ClickHouse HTTP interface port (8443 for HTTPS, 8123 for HTTP)
database	string	Yes	Database name to connect to
username	string	Yes	ClickHouse username
password	string	No	ClickHouse password
secure	boolean	No	Use a secure HTTPS connection (default: true)
table	string	Yes	Current table name
newTable	string	Yes	New table name

Output

Parameter	Type	Description
message	string	Operation status message

ClickHouse Optimize Table

Trigger a merge of table parts via OPTIMIZE TABLE

Inputs and outputs

Input

Parameter	Type	Required	Description
host	string	Yes	ClickHouse server hostname (e.g., your-instance.clickhouse.cloud)
port	number	Yes	ClickHouse HTTP interface port (8443 for HTTPS, 8123 for HTTP)
database	string	Yes	Database name to connect to
username	string	Yes	ClickHouse username
password	string	No	ClickHouse password
secure	boolean	No	Use a secure HTTPS connection (default: true)
table	string	Yes	Table to optimize
final	boolean	No	Force a merge to a single part using FINAL

Output

Parameter	Type	Description
message	string	Operation status message

ClickHouse List Partitions

List active partitions for a ClickHouse table

Inputs and outputs

Input

Parameter	Type	Required	Description
host	string	Yes	ClickHouse server hostname (e.g., your-instance.clickhouse.cloud)
port	number	Yes	ClickHouse HTTP interface port (8443 for HTTPS, 8123 for HTTP)
database	string	Yes	Database name to connect to
username	string	Yes	ClickHouse username
password	string	No	ClickHouse password
secure	boolean	No	Use a secure HTTPS connection (default: true)
table	string	Yes	Table name to inspect partitions for

Output

Parameter	Type	Description
message	string	Operation status message
rows	array	Array of rows returned from the query
rowCount	number	Number of rows returned

ClickHouse Drop Partition

Drop a partition from a ClickHouse table

Inputs and outputs

Input

Parameter	Type	Required	Description
host	string	Yes	ClickHouse server hostname (e.g., your-instance.clickhouse.cloud)
port	number	Yes	ClickHouse HTTP interface port (8443 for HTTPS, 8123 for HTTP)
database	string	Yes	Database name to connect to
username	string	Yes	ClickHouse username
password	string	No	ClickHouse password
secure	boolean	No	Use a secure HTTPS connection (default: true)
table	string	Yes	Table name
partition	string	Yes	Partition expression, e.g. '2024-01' or 202401

Output

Parameter	Type	Description
message	string	Operation status message

ClickHouse List Mutations

List mutations (async ALTER UPDATE/DELETE) for the connected database

Inputs and outputs

Input

Parameter	Type	Required	Description
host	string	Yes	ClickHouse server hostname (e.g., your-instance.clickhouse.cloud)
port	number	Yes	ClickHouse HTTP interface port (8443 for HTTPS, 8123 for HTTP)
database	string	Yes	Database name to connect to
username	string	Yes	ClickHouse username
password	string	No	ClickHouse password
secure	boolean	No	Use a secure HTTPS connection (default: true)
table	string	No	Optional table name to filter mutations
onlyRunning	boolean	No	Only show mutations that are still running

Output

Parameter	Type	Description
message	string	Operation status message
rows	array	Array of mutation rows
rowCount	number	Number of rows returned

ClickHouse List Running Queries

List currently running queries on a ClickHouse server

Inputs and outputs

Input

Parameter	Type	Required	Description
host	string	Yes	ClickHouse server hostname (e.g., your-instance.clickhouse.cloud)
port	number	Yes	ClickHouse HTTP interface port (8443 for HTTPS, 8123 for HTTP)
database	string	Yes	Database name to connect to
username	string	Yes	ClickHouse username
password	string	No	ClickHouse password
secure	boolean	No	Use a secure HTTPS connection (default: true)

Output

Parameter	Type	Description
message	string	Operation status message
rows	array	Array of rows returned from the query
rowCount	number	Number of rows returned

ClickHouse Kill Query

Kill a running query by its query ID

Inputs and outputs

Input

Parameter	Type	Required	Description
host	string	Yes	ClickHouse server hostname (e.g., your-instance.clickhouse.cloud)
port	number	Yes	ClickHouse HTTP interface port (8443 for HTTPS, 8123 for HTTP)
database	string	Yes	Database name to connect to
username	string	Yes	ClickHouse username
password	string	No	ClickHouse password
secure	boolean	No	Use a secure HTTPS connection (default: true)
queryId	string	Yes	The query_id of the running query to kill

Output

Parameter	Type	Description
message	string	Operation status message
rows	array	Kill status rows
rowCount	number	Number of rows returned

ClickHouse Table Stats

Get row counts and on-disk size for tables in the connected database

Inputs and outputs

Input

Parameter	Type	Required	Description
host	string	Yes	ClickHouse server hostname (e.g., your-instance.clickhouse.cloud)
port	number	Yes	ClickHouse HTTP interface port (8443 for HTTPS, 8123 for HTTP)
database	string	Yes	Database name to connect to
username	string	Yes	ClickHouse username
password	string	No	ClickHouse password
secure	boolean	No	Use a secure HTTPS connection (default: true)
table	string	No	Optional table name to get stats for

Output

Parameter	Type	Description
message	string	Operation status message
rows	array	Array of table stats rows
rowCount	number	Number of rows returned

ClickHouse List Clusters

List configured clusters, shards, and replicas

Inputs and outputs

Input

Parameter	Type	Required	Description
host	string	Yes	ClickHouse server hostname (e.g., your-instance.clickhouse.cloud)
port	number	Yes	ClickHouse HTTP interface port (8443 for HTTPS, 8123 for HTTP)
database	string	Yes	Database name to connect to
username	string	Yes	ClickHouse username
password	string	No	ClickHouse password
secure	boolean	No	Use a secure HTTPS connection (default: true)

Output

Parameter	Type	Description
message	string	Operation status message
rows	array	Array of cluster node rows
rowCount	number	Number of rows returned