Section 7 / Pattern Recognition
Pattern Spotter
Decision trees and trigger-answer pairs — see the pattern, know the answer.
Which Ingestion Method?
Which Ingestion Method?
├── External DB, need always-fresh replica → Mirroring
├── Cross-cloud, no data copy → OneLake Shortcuts
├── Bulk ETL from 170+ sources → Pipeline + Copy Activity
├── No-code Power Query transforms → Dataflows Gen2
├── Complex Spark transformations → Notebook Activity
└── Real-time events / IoT → Eventstream
Which Storage Option?
Which Storage Option?
├── Spark / data engineering / ML → Lakehouse
├── T-SQL / multi-table transactions → Warehouse
├── Real-time events / KQL → Eventhouse
├── Unstructured files (PDFs, images) → Lakehouse Files section
└── Cross-database T-SQL queries → Warehouse
Which Delta Maintenance Command?
Which Delta Maintenance Command?
├── Too many small files → OPTIMIZE
├── Reclaim storage from old versions → VACUUM
├── Speed up filtered reads → Z-ORDER BY (column)
├── Check table version history → DESCRIBE HISTORY
├── Roll back a bad write → RESTORE TABLE ... TO VERSION
└── Update query planner stats → ANALYZE TABLE
Which Loading Pattern?
Which Loading Pattern?
├── Small reference table → Full load (overwrite)
├── Large fact table, ongoing sync → Incremental (watermark + MERGE)
├── DB with change tracking → CDC-based incremental
├── External DB, always-fresh needed → Mirroring (automatic)
└── Cross-cloud, zero storage cost → Shortcuts (no load needed)
"medallion architecture" or "bronze/silver/gold"→Lakehouse layered design
"V-Order" or "write-time optimisation"→Fabric auto read optimisation
"mssparkutils" or "notebook.run"→Spark notebook utilities
"High Concurrency mode"→Shared Spark session across notebooks
"MERGE INTO" or "upsert"→Incremental load pattern
"near real-time replication" from external DB→Mirroring (CDC-based)
"zero-copy" or "shortcuts"→OneLake Shortcuts
"small file problem"→OPTIMIZE (compact files)
"Z-ORDER" or "data skipping"→Column co-location for filter perf
"VACUUM" or "reclaim storage"→Remove old Delta file versions
"schema evolution" or "mergeSchema"→Delta Lake schema flexibility
"Eventstream" or "real-time ingestion"→Streaming data into Eventhouse
"Fabric domains"→Organise workspaces by business area
"OneLake RBAC" or "folder-level security"→Fine-grained data access control
"deployment pipelines" for Fabric→Dev → Test → Prod promotion
"watermark pattern"→Incremental load tracking
"Data Activator"→Alert triggers on real-time patterns
"time travel" or "DESCRIBE HISTORY"→Delta Lake version history