Unity Catalog

Guidance for Unity Catalog system tables, volumes, and governance.

When to Use This Skill

Use this skill when:

• Working with volumes (upload, download, list files in /Volumes/ )

• Querying lineage (table dependencies, column-level lineage)

• Analyzing audit logs (who accessed what, permission changes)

• Monitoring billing and usage (DBU consumption, cost analysis)

• Tracking compute resources (cluster usage, warehouse metrics)

• Reviewing job execution (run history, success rates, failures)

• Analyzing query performance (slow queries, warehouse utilization)

• Profiling data quality (data profiling, drift detection, metric tables)

Reference Files

Topic File Description

System Tables 5-system-tables.md Lineage, audit, billing, compute, jobs, query history

Volumes 6-volumes.md Volume file operations, permissions, best practices

Data Profiling 7-data-profiling.md Data profiling, drift detection, profile metrics

Quick Start

Volume File Operations (MCP Tools)

List files in a volume

list_volume_files(volume_path="/Volumes/catalog/schema/volume/folder/")

Upload file to volume

upload_to_volume( local_path="/tmp/data.csv", volume_path="/Volumes/catalog/schema/volume/data.csv" )

Download file from volume

download_from_volume( volume_path="/Volumes/catalog/schema/volume/data.csv", local_path="/tmp/downloaded.csv" )

Create directory

create_volume_directory(volume_path="/Volumes/catalog/schema/volume/new_folder")

Enable System Tables Access

-- Grant access to system tables GRANT USE CATALOG ON CATALOG system TO data_engineers; GRANT USE SCHEMA ON SCHEMA system.access TO data_engineers; GRANT SELECT ON SCHEMA system.access TO data_engineers;

Common Queries

-- Table lineage: What tables feed into this table? SELECT source_table_full_name, source_column_name FROM system.access.table_lineage WHERE target_table_full_name = 'catalog.schema.table' AND event_date >= current_date() - 7;

-- Audit: Recent permission changes SELECT event_time, user_identity.email, action_name, request_params FROM system.access.audit WHERE action_name LIKE '%GRANT%' OR action_name LIKE '%REVOKE%' ORDER BY event_time DESC LIMIT 100;

-- Billing: DBU usage by workspace SELECT workspace_id, sku_name, SUM(usage_quantity) AS total_dbus FROM system.billing.usage WHERE usage_date >= current_date() - 30 GROUP BY workspace_id, sku_name;

MCP Tool Integration

Use mcp__databricks__execute_sql for system table queries:

Query lineage

mcp__databricks__execute_sql( sql_query=""" SELECT source_table_full_name, target_table_full_name FROM system.access.table_lineage WHERE event_date >= current_date() - 7 """, catalog="system" )

Best Practices

• Filter by date - System tables can be large; always use date filters

• Use appropriate retention - Check your workspace's retention settings

• Grant minimal access - System tables contain sensitive metadata

• Schedule reports - Create scheduled queries for regular monitoring

Related Skills

• databricks-spark-declarative-pipelines - for pipelines that write to Unity Catalog tables

• databricks-jobs - for job execution data visible in system tables

• databricks-synthetic-data-gen - for generating data stored in Unity Catalog Volumes

• databricks-aibi-dashboards - for building dashboards on top of Unity Catalog data

Resources

• Unity Catalog System Tables

• Audit Log Reference