I am trying to install pgcrypto in pg_catalog schema. But this does not work with postgres 13 or higher since the function gen_random_uuid is globally available. How can I still create my extension?
I am trying:
CREATE EXTENSION IF NOT EXISTS "pgcrypto" WITH SCHEMA pg_catalog CASCADE
I get the error:
ERROR: function "gen_random_uuid" already exists with same argument types.
All functions in pg_catalog are automatically available within other schemas.
Any function with schema pg_catalog can be called by using schema for example pg_catalog.gen_random_uuid(), but also without defining the schema, for example gen_random_uuid().
Function gen_random_uuid() is part of extension pgcrypto, so when you are trying to enable it, it notifies you, that this function is already installed.
CREATE EXTENSION IF NOT EXISTS pgcrypto WITH SCHEMA pg_catalog CASCADE;
On most cases is recommended to install common Postgres extensions into pg_catalog, so these are available within any schema. All objects in pg_catalog are automatically appended to any other schema. For example if you put pgcrypto into public schema, then you have to always use public.gen_random_uuid() within any other schema, which is annoying etc. But if you put it into pg_catalog, then you can call anywhere gen_random_uuid(), which is more useful.
Related
I am working on a multi tenant Spring Boot application using Postgresql and different schemas for tenants. Everything works fine until we need to use Postgresql's extensions, then we got errors about missing types.
ERROR: function text2ltree(character varying) does not exist
Hint: No function matches the given name and argument types. You might need to add explicit type casts.
Position: 266
The extension is installed using Liquibase and I have updated the changesets to perform the following:
CREATE SCHEMA myschema;
CREATE EXTENSION IF NOT EXISTS ltree WITH SCHEMA myschema;
ALTER DATABASE mydb SET search_path TO "$user", myschema
Then I can control where the extension is installed and updating the search path should avoid to specify the schema all the time. I have run the Liquibase migration and check Postgresql configuration for search_path and it works. I can run queries (using Squirrel) without the need to include the schema prefix for the ltree extension types and functions.
It does not work as expected as I still got the same error message. If I explicitly prefix the ltree types and functions with myschema, I got an error indicating that the operator is not found.
ERROR: operator does not exist: myschema.ltree <# myschema.ltree
Hint: No operator matches the given name and argument types. You might need to add explicit type casts.
Position: 263
For multi tenancy, we implement a custom org.hibernate.engine.jdbc.connections.spi.MultiTenantConnectionProvider that sets the schema in the MultitenantConnectionProvider.getAnyConnection() method.
I want to simplify the setup so I want to avoid to include always the extension's schema, besides the search_path configuration, I can not found anything related. Is there a way to implement the described setup to prevent prefixing with the extension schema in all the code?
If I install the extensions in the pg_catalog schema, then everything works as expected. See this answer.
I want to prevent to install the extensions in the pg_catalog schema so, a closer look to the PGConnection class reveals that the method to set the default schemas updates the search_path value to the schema given.
StringBuilder sb = new StringBuilder();
sb.append("SET SESSION search_path TO '");
Utils.escapeLiteral(sb, schema, getStandardConformingStrings());
sb.append("'");
stmt.executeUpdate(sb.toString());
It is escaping the schema argument, therefore if I try to use multiple schemas separated by commas, the whole expression is escaped.
The solution has been to create my own setSchema method in the MultiTenantConnectionProvider class. It does the same as the code above but adding my extensions' schema to the search_path value.
Maybe I'm saying a silliness, but is it possible to create a extension from a superuser - like postgres - in other database with it own schema and owner?
I have a database called sdmed, with two schemas, public and sdmed. I also have a role called sdmed . This role can only create tables.
I would like to create a extension in those database. The extension has functions, tables and types.
If not, what would be the better way to do that?
Edit:
My original question was incomplete. I mean that I want to create extension from user postgres (or a superuser) in other database, with it owner, role and schema. Also, those extension would be used in those database.
I try this one:
First, I create a function only for those schema (sdmed is a database, with a schema called sdmed and it owner is sdmed):
CREATE OR REPLACE FUNCTION sdmed.di_hola()
RETURNS void AS
$BODY$
BEGIN
RAISE NOTICE 'Hola';
END;
$BODY$
LANGUAGE plpgsql VOLATILE
COST 100;
ALTER FUNCTION sdmed.di_hola()
OWNER TO sdmed;
Also (after prepare my own extension)
postgres=# create extension hola;
ERROR: schema "sdmed" does not exist
(The database role and schema sdmed exists)
And if I try from sdmed database:
sdmed=> create extension hola;
ERROR: permission denied to create extension "hola"
HINT: Must be superuser to create this extension.
I would make sdmed a SuperUser, but I would like to avoid that for keep best practices.
I'm not sure I got your question right, but in case you're wondering if it would somehow make the extension not to work properly the answer is: it shouldn't be an issue :)
Since the user sdmed is the owner of the database sdmed, it has access to all objects in this database - no matter who created them! So, objects installed by the function created with the user postgres should work with the user sdmed without any problem.
I'm trying to run an inline query on my database - which has the citext extension installed (using CREATE EXTENSION) - and yet the executed query keeps throwing this error when calling a function:
type "citext" does not exist
DO
LANGUAGE plpgsql
$$
DECLARE
_id INT;
BEGIN
SELECT * FROM "dbo"."MyFunction"(_id, 'some value'::citext);
END;
$$;
If I omit the ::citext cast, it says:
function dbo.MyFunction(integer, unknown) does not exist.
You might need to add explicit type casts.
The citext extension is added, is part of the schema and works with other queries. This keeps coming up randomly - what causes it?
EDIT:
The installed extensions:
extname | nspname
----------+-----------
plpgsql | pg_catalog
citext | public
uuid-ossp | public
Search path:
show search_path;
search_path
-----------
dbo
As suspected, the extension schema is missing from the search_path. Read up on how to set the schema search path in this related answer:
How does the search_path influence identifier resolution and the "current schema"
It seems like your client sets search_path = dbo on connection, which seems to be misconfigured. dbo is something we see a lot for SQL Server (used to be the default schema here or still is?), very untypical for Postgres. Not sure how you got there.
Why do table names in SQL Server start with "dbo"?
One alternative would be to install extensions into the dbo schema as well:
Best way to install hstore on multiple schemas in a Postgres database?
You can even move (most) extensions to a different schema:
ALTER EXTENSION citext SET SCHEMA dbo;
But I would advice to install extensions to a dedicated schema and include it in the search_path.
Leave plpgsql alone in any case. It's installed by default and should should stay in pg_catalog.
One way or another, clean up the mess with varying search_path settings.
As for the second question: that's guided by the rules of Function Type Resolution. The call cannot be resolved, because citext does not have an implicit cast to text.
Related
Is there a way to disable function overloading in Postgres
THis doesn't work, resulting in ERROR: relation "user" does not exist
select * from "user"
This one does
select * from "dbo"."user"
Tables that aren't schema-qualified are searched for on the search_path. This doesn't search every schema. By default it only searches:
pg_catalog (implicitly always first, not listed on search_path)
pg_temp tablespaces (implicit, not listed on search_path)
A schema named after the current user, listed as $user in search_path
The public schema
If you want PostgreSQL to look elsewhere you have to modify the search_path to tell it so, or fully schema-qualify the name.
See the PostgreSQL manual on search_path.
Also, note that unlike some databases the name dbo has no particular significance in PostgreSQL. It's just another name.
I'm on PostgresQL 9.1.1 trying to have the extension unaccent available on all schemas.
So I ran the command CREATE EXTENSION unaccent;. Which works, but only for the current schema set on search_path. So this means if I change the search_path, I no longer can call unaccent. How do I make this extension available to all schemas in a particular database?
Thanks in advance!
CREATE EXTENSION unaccent; installs the extension into the public schema. To make it usable, simply include this to change the search_path:
set search_path = my_schema, public;
Or better create a schema to contain all extensions, then always append that schema to the search_path.
create schema extensions;
-- make sure everybody can use everything in the extensions schema
grant usage on schema extensions to public;
grant execute on all functions in schema extensions to public;
-- include future extensions
alter default privileges in schema extensions
grant execute on functions to public;
alter default privileges in schema extensions
grant usage on types to public;
Now install the extension:
create extension unaccent schema extensions;
Then use include that schema in the search_path
set search_path = my_schema, extensions;
If you don't want to repeat the above for every new database you create, run the above steps while being connected to the template1 database. You can even include the extensions schema in the default search_path by either editing postgresql.conf or using alter system
Had same question, but #Richard Huxton answer led to correct solution:
create extension unaccent schema pg_catalog;
This works!!
As Richard said, pg_catalog is automatically added (silently) to each search_path. Extensions added there will be found.
imho this is much better than schema.func() if the extension is global.
For example, I use a lot of schemae. I use the schema PUBLIC for debugging - everything should be in its own schema. If something is in PUBLIC, it's wrong.
Creating the extension in pg_catalog keeps all the schema clean, and lets the schema itself work as if it were part of the core postgres.
You don't. You can always call it fully qualified if you want to.
SELECT <schema>.<function>(...)
In fact, I believe the only reason the built-in functions are always available is that PG adds pg_catalog to the end of your search_path no matter what you do.