Naming.md

Naming

We define the unique name strategy per resource to ensure it is followed uniformly independently of who is producing metadata, so we can connect lineage from various sources.

Both Jobs and Datasets are in their own namespaces. Job namespaces are related to their schedulers. The namespace for a dataset is the unique name for its datasource.

Datasets

The namespace and name of a datasource can be combined to form a URI (scheme:[//authority]path)

• Namespace = scheme:[//authority] (the datasource)
• Name = path (the datasets)

Data warehouses/data bases

Datasets are called tables. Tables are organized into databases and schemas.

Postgres:

Datasource hierarchy:

• Host
• Port

Naming hierarchy:

• Database
• Schema
• Table

Identifier:

• Namespace: postgres://{host}:{port} of the service instance.
  • Scheme = postgres
  • Authority = {host}:{port}
• Unique name: {database}.{schema}.{table}
  • URI = postgres://{host}:{port}/{database}.{schema}.{table}

MySQL:

Datasource hierarchy:

• Host
• Port

Naming hierarchy:

• Database
• Table

Identifier:

• Namespace: mysql://{host}:{port} of the service instance.
  • Scheme = mysql
  • Authority = {host}:{port}
• Unique name: {database}.{table}
  • URI = mysql://{host}:{port}/{database}.{table}

Trino:

Datasource hierarchy:

• Host
• Port

Naming hierarchy:

• Catalog
• Schema
• Table

Identifier:

• Namespace: trino://{host}:{port} of the service instance.
  • Scheme = trino
  • Authority = {host}:{port}
• Unique name: {catalog}.{schema}.{table}
  • URI = trino://{host}:{port}/{catalog}.{schema}.{table}

Redshift:

Datasource hierarchy:

• Host: examplecluster.<XXXXXXXXXXXX>.us-west-2.redshift.amazonaws.com
• Port: 5439

OR

• Cluster identifier
• Region name
• Port (defaults to 5439)

Naming hierarchy:

• Database
• Schema
• Table

One can interact with Redshift using SQL or Data API. The combination of cluster identifier and region name is the only common unique ID available to both.

Identifier:

• Namespace: redshift://{cluster_identifier}.{region_name}:{port} of the cluster instance.
  • Scheme = redshift
  • Authority = {cluster_identifier}:{port}
• Unique name: {database}.{schema}.{table}
  • URI = redshift://{cluster_identifier}.{region_name}:{port}/{database}.{schema}.{table}

Athena:

Datasource hierarchy:

• Host: athena.{region_name}.amazonaws.com

Naming hierarchy:

• Catalog
• Database
• Table

Identifier:

• Namespace: awsathena://athena.{region_name}.amazonaws.com of the service instance.
  • Scheme = awsathena
  • Authority = athena.{region_name}.amazonaws.com
• Unique name: {catalog}.{database}.{table}
  • URI = awsathena://athena.{region_name}.amazonaws.com/{catalog}.{database}.{table}

Snowflake

See: Object Identifiers — Snowflake Documentation

Datasource hierarchy:

• account name

Naming hierarchy:

• Database: {database name} => unique across the account
• Schema: {schema name} => unique within the database
• Table: {table name} => unique within the schema

Database, schema, table and column names are uppercase in Snowflake. Clients should make sure that they are sending them in uppercase.

Identifier:

• Namespace: snowflake://{account name}
  • Scheme = snowflake
  • Authority = {account name}
• Name: {database}.{schema}.{table}
  • URI = snowflake://{account name}/{database}.{schema}.{table}

BigQuery

See: Creating and managing projects | Resource Manager Documentation Introduction to datasets | BigQuery Introduction to tables | BigQuery

Datasource hierarchy:

• bigquery

Naming hierarchy:

• Project Name: {project name} => is not unique
• Project number: {project number} => numeric: is unique across Google cloud
• Project ID: {project id} => readable: is unique across Google cloud
• dataset: {dataset name} => is unique within a project
• table: {table name} => is unique within a dataset

Identifier:

• Namespace: bigquery
  • Scheme = bigquery
  • Authority =
• Unique name: {project id}.{dataset name}.{table name}
  • URI = bigquery:{project id}.{dataset name}.{table name}

Azure Synapse:

Datasource hierarchy:

• Host: <XXXXXXXXXXXX>.sql.azuresynapse.net
• Port: 1433
• Database: SQLPool1

Naming hierarchy:

• Schema
• Table

Identifier:

• Namespace: sqlserver://{host}:{port};database={database};
  • Scheme = sqlserver
  • Authority = {host}:{port}
• Unique name: {schema}.{table}
  • URI = sqlserver://{host}:{port};database={database}/{schema}.{table}

Azure Cosmos DB:

Datasource hierarchy: azurecosmos://%s.documents.azure.com/dbs/%s

• Host: <XXXXXXXXXXXX>.documents.azure.com
• Database

Naming hierarchy:

• Schema
• Table

Identifier:

• Namespace: azurecosmos://{host}/dbs/{database}
  • Scheme = azurecosmos
  • Authority = {host}
• Unique name: /colls/{table}
  • URI = azurecosmos://{host}.documents.azure.com/dbs/{database}/colls/{table}

Azure Data Explorer:

Datasource hierarchy:

• Host: <clustername>.<clusterlocation>
• Database
• Table

Naming hierarchy:

• Database
• Table

Identifier:

• Namespace: azurekusto://{host}.kusto.windows.net/{database}
  • Scheme = azurekusto
• Unique name: {database}/{table}
  • URI = azurekusto://{host}.kusto.windows.net/{database}/{table}

Distributed file systems/blob stores

GCS

Datasource hierarchy: none, naming is global

Naming hierarchy:

• bucket name => globally unique
• Path

Identifier :

• Namespace: gs://{bucket name}
  • Scheme = gs
  • Authority = {bucket name}
• Unique name: {path}
  • URI = gs://{bucket name}{path}

S3

Naming hierarchy:

• bucket name => globally unique
• Path

Identifier :

• Namespace: s3://{bucket name}
  • Scheme = s3
  • Authority = {bucket name}
• Unique name: {path}
  • URI = s3://{bucket name}{path}

HDFS

Naming hierarchy:

• Namenode: host + port
• Path

Identifier :

• Namespace: hdfs://{namenode host}:{namenode port}
  • Scheme = hdfs
  • Authority = {namenode host}:{namenode port}
• Unique name: {path}
  • URI = hdfs://{namenode host}:{namenode port}{path}

DBFS (Databricks File System)

Naming hierarchy:

• workspace name: globally unique
• Path

Identifier :

• Namespace: hdfs://{workspace name}
  • Scheme = hdfs
  • Authority = workspace name
• Unique name: {path}
  • URI = hdfs://{workspace name}{path}

ABFSS (Azure Data Lake Gen2)

Naming hierarchy:

• service name => globally unique
• Path

Identifier :

• Namespace: abfss://{container name}@{service name}
  • Scheme = abfss
  • Authority = service name
• Unique name: {path}
  • URI = abfss://{container name}@{service name}{path}

WASBS (Azure Blob Storage)

Naming hierarchy:

• service name => globally unique
• Path

Identifier :

• Namespace: wasbs://{container name}@{service name}
  • Scheme = wasbs
  • Authority = service name
• Unique name: {path}
  • URI = wasbs://{container name}@{service name}{path}

Local file system

Datasource hierarchy:

• IP
• Port

Naming hierarchy:

• Path

Identifier :

• Namespace: file://{IP}:{port}
  • Scheme = file
  • Authority = {IP}:{port}
• Unique name: {path}
  • URI = file://{IP}:{port}{path}

Jobs

Context

A Job is a recurring data transformation with inputs and outputs. Each execution is captured as a Run with corresponding metadata. A Run event identifies the Job it is an instance of by providing the job’s unique identifier. The Job identifier is composed of a Namespace and a Name. The job name is unique within that namespace.

The core property we want to identify about a Job is how it changes over time. Different schedules of the same logic applied to different datasets (possibly with different parameters) are different jobs. The notion of a job is tied to a recurring schedule with specific inputs and outputs. It could be an incremental update or a full reprocess or even a streaming job.

If the same code artifact (for example a Spark jar or a templated SQL query) is used in the context of different schedules with different input or outputs, then they are different jobs. We are interested first in how they affect the datasets they produce.

Job Namespace and constructing job names

Jobs have a name that is unique to them in their namespace by construction.

The Namespace is the root of the naming hierarchy. The job name is constructed to identify the job within that namespace.

Example:

• Airflow:
  • Namespace: the namespace is assigned to the Airflow instance. Ex: airflow-staging, airflow-prod
  • Job: each task in a DAG is a job. name: {dag name}.{task name}
• Spark:
  • Namespace: the namespace is provided as a configuration parameter as in Airflow. If there's a parent job, we use the same namespace, otherwise it is provided by configuration.
  • Spark app job name: the spark.app.name
  • Spark action job name: {spark.app.name}.{node.name}

Parent job run: a nested hierarchy of Jobs

It is often the case that jobs are part of a nested hierarchy. For example, an Airflow DAG contains tasks. An instance of the DAG is finished when all of the tasks are finished. Similarly, a Spark job can spawn multiple actions, each of them running independently. Additionally, a Spark job can be launched by an Airflow task within a DAG.

Since what we care about is identifying the job as rooted in a recurring schedule, we want to capture that connection and make sure that we treat the same application logic triggered at different schedules as different jobs. For example: if an Airflow DAG runs individual tasks per partition (e.g., market segments) using the same underlying job logic, they will be tracked as separate jobs.

To capture this, a run event provides a ParentRun facet referring to the parent Job and Run. This allows tracking a recurring job from the root of the schedule for which it is running. If there's a parent job, we use the same namespace, otherwise it is provided by configuration.

Example:

{
  "run": {
    "runId": "run_uuid"
  },
  "job": {
    "namespace": "job_namespace",
    "name": "job_name"
  }
}

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