Tables Reference

Technical reference for tables in Confidence Metrics.

This section provides technical specifications and reference information for assignment tables, fact tables, and dimension tables.

For conceptual explanations of tables, see Tables in the Metrics Concepts page.

Column Types

All tables use these column type specifications:

Type	Description	Example Use
COLUMN_TYPE_STRING	Text values	User IDs, country codes, product names
COLUMN_TYPE_INTEGER	Whole numbers	Count values, age, quantity
COLUMN_TYPE_DOUBLE	Decimal numbers	Revenue, ratings, percentages
COLUMN_TYPE_BOOLEAN	True/false values	Conversion flags, feature enabled
COLUMN_TYPE_TIMESTAMP	Date and time	Event timestamps, created dates
COLUMN_TYPE_DATE	Date only	Birth dates, enrollment dates

Assignment Tables

Required Fields

Field	Type	Description
timestampColumn	Column	When the assignment occurred
entityColumnMapping	ColumnMapping	Which entity was assigned
exposureKeyColumn	Column	Identifies the experiment/feature
variantKeyColumn	Column	Which variant was assigned

Data Delivery Strategies

Automatic

Continuously updates data based on incremental checks:

{
  "strategy": "AUTOMATIC",
  "automaticUpdateConfig": {
    "incrementDuration": "P13H",
    "commitDelay": "P13H"
  }
}

• incrementDuration: How frequently to check for new data (ISO 8601 duration)
• commitDelay: Buffer time before considering data complete

Daily

Updates once per day at a scheduled time:

{
  "strategy": "DAILY",
  "dailyUpdateConfig": {}
}

Fact Tables

Required Fields

Field	Type	Description
name	string	Unique identifier for the table
displayName	string	Human-readable name
sql	string	SQL query selecting fact rows
timestampColumn	Column	When the measurement occurred
entities	ColumnMapping[]	Entity columns (at least one required)
measurements	Column[]	Measurement columns (at least one required)

Column Specifications

Each column requires:

• name: Column name in query results
• type: Column type (from table above)
• repeated: Boolean indicating if column contains arrays

Table States

State	Description
CREATING	Initial validation in progress
ACTIVE	Ready for use in metrics
FAILED	Validation failed, check error messages

Dimension Tables

Required Fields

Field	Type	Description
displayName	string	Human-readable name
sql	string	SQL query selecting dimension rows
timestampColumn	Column	When the dimension value applies
entityColumnMapping	ColumnMapping[]	Entity columns (at least one required)
dimensions	Column[]	Dimension columns (at least one required)

Dimension Column Types

Dimensions typically use:

• STRING: Categorical values (country, platform, tier)
• BOOLEAN: Binary attributes (is_premium, is_active)
• INTEGER: Numeric categories (age_group_code, tier_level)

Table States

Same as fact tables: CREATING, ACTIVE, FAILED

Column Mapping Structure

Column mappings connect query results to entities:

{
  "column": {
    "name": "user_id",
    "type": "COLUMN_TYPE_STRING",
    "repeated": false
  },
  "entity": "entities/user"
}

Best Practices

SQL Queries

• Use SELECT * sparingly: Explicitly specify columns for better performance
• Add WHERE clauses: Filter data at query time to reduce processing
• Use partitioning: Leverage data warehouse partitioning for efficiency
• Test queries: Validate SQL in your data warehouse before creating tables

Data Quality

• Validate timestamps: Ensure timestamp columns are in the correct format
• Handle NULLs: Decide how to handle NULL values in measurements
• Check data types: Verify column types match your schema expectations
• Monitor failures: Review failed tables and fix SQL or schema issues