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)
| Tool | Usage |
|---|---|
list_volume_files | list_volume_files(volume_path="/Volumes/catalog/schema/volume/path/") |
get_volume_folder_details | get_volume_folder_details(volume_path="catalog/schema/volume/path", format="parquet") - schema, row counts, stats |
upload_to_volume | upload_to_volume(local_path="/tmp/data/*", volume_path="/Volumes/.../dest") |
download_from_volume | download_from_volume(volume_path="/Volumes/.../file.csv", local_path="/tmp/file.csv") |
create_volume_directory | create_volume_directory(volume_path="/Volumes/.../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