ClickHouse data sources

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This article refers to BaseModel accessed via Docker container. Please refer to Snowflake Native App section if you are using BaseModel as SF GUI application.

Various data sources are specified in the YAML file used by the pretrain function and configured by the entries in data_location section. Below is an example code that should be adapted to your configuration.

data_location:
  database_type: clickhouse
    connection_params:
      host: 'HOST_IP'
    schema_name: SCHEMA
    table_name: TABLE_NAME

• database_type : str, required
  No default value.
  Information about the database type or source file. All data tables should be stored in the same type. Set to clickhouse.
  
• connection_params : dict, required
  Configures the connection to the database. For ClickHouse its keyword arguments are:
  
  • host : str, required
    No default value.
    The hostname or IP address of the ClickHouse server. If not set, localhost will be used.
    
• schema_name : str, required
  No default value.
  Specifies the name of the database to use to create features.
  
• table_name : str, required
  No default value.
  Specifies the table to use to create features. Example: customers.
  

The connection_params should be set separately in each data_location block, for each data source.

The following example demonstrates the connection to ClickHouse in the context of a simple configuration with two data sources.

data_sources:
  -type: main_entity_attribute
   main_entity_column: UserID
   name: customers
   data_location:
     database_type: clickhouse
     connection_params:
       host: '123.45.67.890'
     schema_name: some_schema
     table_name: customers
   disallowed_columns: [CreatedAt]
  -type: event
   main_entity_column: UserID
   name: purchases
   date_column: 
     name: Timestamp
   data_location:
     database_type: clickhouse
     connection_params:
       host: '123.45.67.890'
     schema_name: some_schema
     table_name: purchases
   where_condition: "Timestamp >= today() - 365"
   sql_lambdas: 
     - alias: price_float
       expression: "TO_DOUBLE(price)"

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Learn More

The detailed description of optional fields such as disallowed_columns, where_condition, sql_lambda, and many others is provided here