redshift-guide
Amazon Redshift Guide
Redshift is NOT PostgreSQL (read first)
Redshift speaks PostgreSQL's wire protocol and shares much of its surface syntax, so
LLMs assume PostgreSQL behavior carries over — it frequently does not. Divergences span
system tables (pg_catalog is incomplete), DDL (no indexes, no sequences), functions
(string_agg, SUBSTR on tables, leader-node-only functions), types (a text column
becomes VARCHAR(256)), and comparison semantics (trailing blanks, unenforced constraints). Assume
divergence and verify against the reference below — do not answer from PostgreSQL habit.
Common PostgreSQL→Redshift divergences are in references/redshift-sql-syntax.md.
Works best with the AWS MCP server — it runs the AWS CLI and Redshift Data API calls below in a sandboxed, audit-logged environment. All guidance here is plain AWS CLI and SQL and works without it.