I have a postgres database with multiple schemas. When I connect to the database from a shell with psql and I run \dt it uses the default connection schema which is public. Is there a flag I can specify or how can I change the schema?
10 Answers
In PostgreSQL the system determines which table is meant by following a search path, which is a list of schemas to look in.
The first matching table in the search path is taken to be the one wanted, otherwise, if there is no match a error is raised, even if matching table names exist in other schemas in the database.
To show the current search path you can use the following command:
SHOW search_path;And to put the new schema in the path, you could use:
SET search_path TO myschema;Or if you want multiple schemas:
SET search_path TO myschema, public;Reference:
0\l - Display database
\c - Connect to database
\dn - List schemas
\dt - List tables inside public schemas
\dt schema1. - List tables inside particular schemas. For eg: 'schema1'.Do you want to change database?
\l - to display databases
\c - connect to new databaseUpdate.
I've read again your question. To display schemas
\dn - list of schemasTo change schema, you can try
SET search_path TOif you in psql just type
set schema 'temp';and after that \d shows all relations in "temp
2Use schema name with period in psql command to obtain information about this schema.
Setup:
test=# create schema test_schema;
CREATE SCHEMA
test=# create table test_schema.test_table (id int);
CREATE TABLE
test=# create table test_schema.test_table_2 (id int);
CREATE TABLEShow list of relations in test_schema:
test=# \dt test_schema. List of relations Schema | Name | Type | Owner
-------------+--------------+-------+---------- test_schema | test_table | table | postgres test_schema | test_table_2 | table | postgres
(2 rows)Show test_schema.test_table definition:
test=# \d test_schema.test_table
Table "test_schema.test_table" Column | Type | Modifiers
--------+---------+----------- id | integer | Show all tables in test_schema:
test=# \d test_schema.
Table "test_schema.test_table" Column | Type | Modifiers
--------+---------+----------- id | integer |
Table "test_schema.test_table_2" Column | Type | Modifiers
--------+---------+----------- id | integer | etc...
2This is old, but I put exports in my alias for connecting to the db:
alias schema_one.con="PGOPTIONS='--search_path=schema_one' psql -h host -U user -d database etc"And for another schema:
alias schema_two.con="PGOPTIONS='--search_path=schema_two' psql -h host -U user -d database etc"quick solution could be:
SELECT your_db_column_name from "your_db_schema_name"."your_db_tabel_name";key word :
SET search_path TOexample :
SET search_path TO your_schema_name;if playing with psql inside docker exec it like this:
docker exec -e "PGOPTIONS=--search_path=<your_schema>" -it docker_pg psql -U user db_namePostgreSQL 14 Debian
postgres@ovhswift:~$ psql
psql (14.0 (Debian 14.0-1.pgdg100+1))
Type "help" for help.
postgres=# create database test;
CREATE DATABASE
postgres=# \c test
You are now connected to database "test" as user "postgres".
test=# create schema tests;
CREATE SCHEMA
test=# \dt
Did not find any relations.
test=# create table pubtable (id integer);
CREATE TABLE
test=# create table tests.schematable (id integer);
CREATE TABLE
test=# \dt List of relations Schema | Name | Type | Owner
--------+----------+-------+---------- public | pubtable | table | postgres
(1 row)
test=# \dt tests.
Did not find any relation named "tests.".
test=# \dt tests
Did not find any relation named "tests".
test=# \dt 'tests.'
Did not find any relation named "tests.".
test=# \dt 'tests.*' List of relations Schema | Name | Type | Owner
--------+-------------+-------+---------- tests | schematable | table | postgres
(1 row)
test=# \dt 'tests*'
Did not find any relation named "tests*".
test=# \dt 'tests.*' List of relations Schema | Name | Type | Owner
--------+-------------+-------+---------- tests | schematable | table | postgres
(1 row)Ditto for \dv etc. to see the views in the schema
