How to fix relation 'table_name' does not exist in PostgreSQL

\dt

SELECT table_name FROM information_schema.tables WHERE table_schema = 'public';

SELECT table_name FROM information_schema.tables WHERE table_schema = 'your_schema_name';

-- If table was created without quotes (case-insensitive)
SELECT * FROM users;  -- works
SELECT * FROM USERS;  -- also works

-- If table was created WITH quotes (case-sensitive)
SELECT * FROM "MyTable";  -- must use exact casing
SELECT * FROM "mytable";  -- fails

SELECT schemaname, tablename FROM pg_tables WHERE tablename ILIKE 'your_table_name';

-- Incorrect (looks in public schema by default)
SELECT * FROM orders;

-- Correct (if orders is in app_schema)
SELECT * FROM app_schema.orders;

SET search_path TO app_schema, public;
SELECT * FROM orders;  -- now works

ALTER ROLE your_user SET search_path TO app_schema, public;

# Check current database
\c

# Connect to correct database
psql -U username -d correct_database_name -h localhost

-- View permissions
\dp table_name

-- Grant SELECT permission
GRANT SELECT ON table_name TO your_user;

-- Grant all permissions
GRANT ALL PRIVILEGES ON table_name TO your_user;

GRANT USAGE ON SCHEMA schema_name TO your_user;

-- Good: simple, unambiguous
CREATE TABLE users (
  id SERIAL PRIMARY KEY,
  email VARCHAR(255)
);

SELECT * FROM users;  -- always works
SELECT * FROM USERS;  -- also works

-- Avoid: quoted names create case sensitivity
CREATE TABLE "Users" (...);  -- creates case-sensitive table
SELECT * FROM "Users";  -- must use exact casing