PostgreSQL Error 3D000

SQLSTATE

3D000

Condition name

invalid_catalog_name

Product

PostgreSQL

Versions

PostgreSQL 13 to 18 (SQL-level examples run on PostgreSQL 18.6 in PGlite)

Category

Connections, Authentication & Privileges

Last reviewed

24 October 2026

What it means

SQLSTATE 3D000 means the database named in the connection or in a statement does not exist on this server.

A PostgreSQL connection is always to one database, named in the connection string. If no database with that name exists on the server, the login ends with FATAL: database "..." does not exist and SQLSTATE 3D000 (invalid_catalog_name). The documentation points out a common trap: if you do not specify a database name, it defaults to the database user name, so psql -U andym with no database tries to connect to a database called andym. Connection parameters are taken literally, so the name must match exactly, including upper and lower case.

Inside a session, statements that name a database (ALTER DATABASE, DROP DATABASE, GRANT ... ON DATABASE, CREATE DATABASE ... TEMPLATE, functions such as pg_database_size) raise the same SQLSTATE as a normal ERROR. In SQL, unquoted names are folded to lower case: a database created as "SalesApp" must be written with the quotes, or PostgreSQL looks for salesapp. PostgreSQL has no cross-database queries, so a three-part name such as otherdb.public.t is not a way to reach another database.

Common causes

• A typo or wrong environment in the database name (dbname in the connection string, the PGDATABASE environment variable, or the application configuration).
• No database given, so the client used the role name as the database name and no such database exists.
• The database has not been created yet on this server: a new environment, a restore that has not run, or a container whose initialisation script did not create it.
• The client is connected to a different server or port than intended, which has other databases.
• A mixed-case database name written without double quotes in SQL, so PostgreSQL looks for the lower-case name.
• A script runs DROP or ALTER DATABASE on a database that was already removed or renamed.

Diagnose it

Read-only These queries only read the system catalogs (pg_catalog, information_schema) and statistics views such as pg_stat_activity and pg_locks. They do not change data, roles or settings, so they are safe to run first.

SELECT datname, datallowconn
FROM pg_database
ORDER BY datname;

SELECT datname
FROM pg_database
WHERE lower(datname) = lower('SalesApp');

SELECT current_database(),
       current_user,
       current_setting('port') AS port,
       current_setting('data_directory') AS data_directory;

How to fix it

Each fix is labelled with what it changes. Try read-only checks and the least invasive fix first, and test changes outside production.

CREATE DATABASE testdb OWNER andym;

ALTER DATABASE "SalesApp" SET work_mem = '64MB';

DROP DATABASE IF EXISTS old_reporting;

Examples

Connecting to a database that does not exist

Shown as documented in the PostgreSQL documentation (Client Authentication, Authentication Problems). The same happens with no dbname at all when no database is named after the role, because the database name then defaults to the user name. This example needs a running PostgreSQL server (a login to a named database), which PGlite does not provide, so it was not reproduced here.

-- From a shell:
-- psql "host=server.joe.com dbname=testdb user=andym"

FATAL:  database "testdb" does not exist

A mixed-case database name without quotes

CREATE DATABASE "SalesApp";

ALTER DATABASE SalesApp SET work_mem = '64MB';

ERROR:  database "salesapp" does not exist

Dropping a database that is not there

DROP DATABASE nosuchdb;

ERROR:  database "nosuchdb" does not exist

Creating a database from a missing template

CREATE DATABASE copydb TEMPLATE nosuchtemplate;

ERROR:  template database "nosuchtemplate" does not exist

How to prevent it

Name the database explicitly in every connection string and keep one source of connection settings per environment. Create databases in the provisioning step (an init script, infrastructure code or a migration tool) so applications never start before their database exists.

Use lower-case database names without special characters, and use IF EXISTS / IF NOT EXISTS patterns in scripts that may run more than once.

Common questions

Learn more on CodeWithSQL

• Install PostgreSQL
• Run PostgreSQL in Docker

Official documentation

• Authentication problems
• Managing databases: overview
• CREATE DATABASE
• DROP DATABASE

Last technically reviewed 24 October 2026; examples and diagnostics run on PostgreSQL 18.6 documentation; SQL-level parts in PGlite 0.5.11. SQL-level examples were run in PGlite (PostgreSQL compiled to WebAssembly); examples that need a running server are shown as documented in the PostgreSQL documentation.