snowflake-development

# Snowflake Development Snowflake SQL, data pipelines, Cortex AI, and Snowpark Python development. Covers the colon-prefix rule, semi-structured data, MERGE upserts, Dynamic Tables, Streams+Tasks, Cortex AI functions, agent specs, performance tuning, and security hardening. > Originally contributed by [James Cha-Earley](https://github.com/jamescha-earley) — enhanced and integrated by the claude-skills team. ## Quick Start ```bash # Generate a MERGE upsert template python scripts/snowflake_query_helper.py merge --target customers --source staging_customers --key customer_id --columns name,email,updated_at # Generate a Dynamic Table template python scripts/snowflake_query_helper.py dynamic-table --name cleaned_events --warehouse transform_wh --lag "5 minutes" # Generate RBAC grant statements python scripts/snowflake_query_helper.py grant --role analyst_role --database analytics --schemas public,staging --privileges SELECT,USAGE ``` --- ## SQL Best Practices ### Naming and Style - Use `snake_case` for all identifiers. Avoid double-quoted identifiers -- they force case-sensitive names that require constant quoting. - Use CTEs (`WITH` clauses) over nested subqueries. - Use `CREATE OR REPLACE` for idempotent DDL. - Use explicit column lists -- never `SELECT *` in production. Snowflake's columnar storage scans only referenced columns, so explicit lists reduce I/O. ### Stored Procedures -- Colon Prefix Rule In SQL stored procedures (BEGIN...END blocks), variables and para...