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42P06ERRORTier 2 — Caution✅ HIGH confidence

duplicate schema

Category: Syntax Error or Access Rule ViolationVersions: All Postgres versions

What this means

SQLSTATE 42P06 is raised when CREATE SCHEMA is called with a name that already exists and IF NOT EXISTS is not specified.

Why it happens

  1. 1CREATE SCHEMA specifying a schema name that already exists in the database

How to reproduce

Creating a schema that already exists.

trigger — this will ERROR
CREATE SCHEMA myschema; -- myschema already exists
ERROR: schema "myschema" already exists

Fix 1: Use CREATE SCHEMA IF NOT EXISTS

In migration scripts that may run multiple times.

fix
CREATE SCHEMA IF NOT EXISTS myschema;

Why this works

IF NOT EXISTS silently succeeds if the schema already exists, making the command idempotent.

Sources

📚 Official docs: https://www.postgresql.org/docs/current/errcodes-appendix.html

🔧 Source ref: Class 42 — Syntax Error or Access Rule Violation (Postgres-specific)

Confidence assessment

✅ HIGH confidence

Postgres-specific. Stable across all versions.

See also

📄 Reference pages

CREATE SCHEMASchema Management
⚙️ This error reference was generated with AI assistance and reviewed for accuracy. Examples are provided to illustrate common scenarios and may not cover every case. Always test fixes in a development environment before applying to production. Spotted an error? Suggest a correction →