What does Atlan crawl from ClickHouse?
Atlan extracts metadata for Databases, Schemas, Tables, Views, and Columns from ClickHouse and maps each property to its internal asset model. The tables below list which ClickHouse properties are read and how they appear on the corresponding Atlan asset.
Once you have crawled ClickHouse, you can use connector-specific filters for quick asset discovery.
Databases
ClickHouse uses a single-level database hierarchy. Atlan maps the top-level catalog as default to its Database asset type, and maps each ClickHouse database to the Schema asset type.
| Source property | Atlan property | Where in Atlan |
|---|---|---|
default (catalog) | name | asset preview and profile, overview sidebar |
SCHEMA_COUNT | schemaCount | asset filters |
Schemas
Atlan maps ClickHouse databases to its Schema asset type.
| Source property | Atlan property | Where in Atlan |
|---|---|---|
system.databases.name | name | asset preview and profile, overview sidebar |
TABLE_COUNT | tableCount | asset preview and profile |
VIEW_COUNT | viewsCount | asset preview and profile |
default (catalog) | databaseName | asset preview and profile, overview sidebar |
Tables
Atlan maps tables from ClickHouse to its Table asset type.
| Source property | Atlan property | Where in Atlan |
|---|---|---|
system.tables.name | name | asset preview and profile, overview sidebar |
system.tables.engine | definition (engine type) | asset profile, overview sidebar |
COLUMN_COUNT | columnCount | asset preview and profile, overview sidebar |
system.tables.total_rows | rowCount | asset preview and profile, overview sidebar |
system.tables.total_bytes | sizeBytes | asset preview and profile, overview sidebar |
system.tables.partition_key | partitionStrategy | API only |
system.tables.sorting_key | custom metadata | API only |
system.tables.primary_key | custom metadata | API only |
Views
Atlan maps views from ClickHouse to its View asset type. This includes both regular views and materialized views.
| Source property | Atlan property | Where in Atlan |
|---|---|---|
system.tables.name | name | asset preview and profile, overview sidebar |
COLUMN_COUNT | columnCount | asset preview and profile, overview sidebar |
system.tables.create_table_query | definition | asset profile and overview sidebar |
system.tables.engine | subType (VIEW or MATERIALIZED VIEW) | API only |
Columns
Atlan maps columns from ClickHouse to its Column asset type.
| Source property | Atlan property | Where in Atlan |
|---|---|---|
system.columns.name | name | asset profile and filter, overview sidebar |
system.columns.comment | description | asset profile and filter, overview sidebar |
system.columns.position | order | parent asset profile |
system.columns.type | dataType | asset preview and filter, overview sidebar, parent asset profile |
system.columns.is_in_primary_key | isPrimary | asset preview and filter, overview sidebar, parent asset profile |
Nullable(...) type detection | isNullable | API only |
system.columns.numeric_scale | numericScale | API only |
system.columns.numeric_precision | precision | API only |