What problem does it solve? Modeling non-trivial analytics scenarios in Snowflake Semantic Views—year-over-year comparisons, SCD2 temporal joins, snapshot balances, funnel pipelines, multi-path relationships—requires specific YAML constructs that are easy to get wrong, producing deploy errors or silently inflated numbers. ## Core Features & Use Cases - Pattern Catalog: 14 documented patterns (time intelligence, ASOF/range joins, semi-additive metrics, window metrics, accumulating snapshots, role-playing dimensions, derived metrics, multi-fact tables, computed join keys, AI metadata, diagnostics) each with working YAML snippets and binding gotchas. - Diagnostics Guide: Maps six failure modes (ambiguous paths, fan traps, missing relationships, duplicate names, wrong cardinality, forgotten semi-additivity) to exact error messages and broken/fixed YAML pairs. - Guided Workflow: Steps for retrieving the target SV, adapting snippet placeholders, dry-run validating with SYSTEM$CREATE_SEMANTIC_VIEW_FROM_YAML, and smoke-testing after deploy. - Use Case: A user asks for a loan funnel metric (applied → reviewed → decided → funded). The skill loads the accumulating_snapshot snippet, adapts it to the target SV's tables, validates the YAML, and verifies each stage metric buckets by its own milestone date. ## Quick Start Load this skill and ask to add a year-over-year revenue comparison to my semantic view YAML.