I have a schema called application. Is there a way that, rather than using the syntax
SELECT * FROM application.table
I can set the default schema so that I can just use
SELECT * FROM table
It would be the same idea as a using statement I suppose.
The default schema for all sql server users is "dbo", You can alter the default schema for a user by using commands ALTER USER
ALTER USER UserName WITH DEFAULT_SCHEMA = application;
It will be great to have a use statement for schemas.
You can vote the feature suggestion on Microsoft connect.
Related
Can I use CREATE SCHEMA AUTHORIZATION for something other than the current user's schema?
I can do the following:
CREATE USER MAIN_USER
IDENTIFIED BY main_user_pass;
GRANT CREATE SESSION TO MAIN_USER;
GRANT CREATE TABLE TO MAIN_USER;
ALTER SESSION SET CURRENT_SCHEMA = MAIN_USER;
Query 1:
SELECT USER FROM DUAL;
Result 1:
SYS
Query 2:
SELECT sys_context( 'userenv', 'current_schema') FROM dual;
Result 2:
MAIN_USER
I can do this:
CREATE SCHEMA AUTHORIZATION SYS
CREATE TABLE new_product
(color VARCHAR2(10) PRIMARY KEY);
Result:
Schema AUTHORIZATION created.
But when I try to do this, an error appears:
CREATE SCHEMA AUTHORIZATION MAIN_USER
CREATE TABLE new_product
(color VARCHAR2(10) PRIMARY KEY);
Result:
ORA-02421: missing or invalid schema authorization identifier
02421. 00000 - "missing or invalid schema authorization identifier"
*Cause: the schema name is missing or is incorrect in an authorization
clause of a create schema statement.
*Action: If the name is present, it must be the same as the current
schema.
The error message is pretty clear: you can't do that. From the documentation:
The schema name must be the same as your Oracle Database username.
Setting current_schema only changes the default schema name prepended to an object reference in a SQL command that isn't fully qualified, so after setting it to MAIN_USER, this command:
select * table table_a;
would be interpreted as
select * from main_user.table_a;
instead of
select * from sys.table_a;
Setting current_schema doesn't actually change your logged in identity or affect your privileges in any way, and if sys can't execute a command like that against another schema then nobody can do it.
Can I use CREATE SCHEMA AUTHORIZATION for something other than the current user's schema?
No, you can't. The documentation says:
Use the CREATE SCHEMA statement to create multiple tables and views and perform multiple grants in your own schema in a single transaction.
This statement lets you populate your schema ...
Specify the name of the schema. The schema name must be the same as your Oracle Database username.
You have to be connected as the schema owner, so user returns MAIN_USER. Just changing your current schema with ALTER SESSION SET CURRENT_SCHEMA is not sufficient.
It also says:
To issue a CREATE SCHEMA statement, you must have the privileges necessary to issue the included statements.
and you have granted CREATE TABLE so that should work once you connect as that user. But it means you can't rely on the privileged SYS user's CREATE ANY privs to bypass the schema grants, which might have been an advantage had it been allowed to work as you hoped; if you want your user to end up without those privileges you'll have to grant them, run CREATE SCHEMA as that user, then revoke them again. Or go back to individual CREATE object statements, which you can run for another user as SYS - but without the all-or-nothing single-transaction benefit you get from CREATE SCHEMA.
I am new with DB2.
I am not able to get data from a table without using the schema name. If I use a schema name with table name, I am able to fetch data.
Example:
SELECT * FROM TABLE_NAME;
It is giving me error, while
SELECT FROM SCHEMA_NAME.TABLE_NAME;
is fetching a result.
What do I have to set up not to always have to use the schema name?
By default, your username is used as the schema name for unqualified object names. You can see the current schema with, e.g. VALUES CURRENT SCHEMA. You can change the current schema for you current session with SET SCHEMA new_schema_name, or via e.g. a JDBC connection parameter. Most query tools also have a place to specify/change the current schema.
See the manual page for SET SCHEMA https://www.ibm.com/support/knowledgecenter/en/SSEPGG_11.1.0/com.ibm.db2.luw.sql.ref.doc/doc/r0001016.html
The full rules for the qualification of unqualified objects is here https://www.ibm.com/support/knowledgecenter/en/SSEPGG_11.1.0/com.ibm.db2.luw.sql.ref.doc/doc/r0000720.html#r0000720__unq-alias
E.g.
Unqualified alias, index, package, sequence, table, trigger, and view names are implicitly qualified by the default schema.
However, you can create a public alias for a table, module or sequence if you wish to be able to reference it regardless of your CURRENT SCHEMA value.
https://www.ibm.com/support/knowledgecenter/SSEPGG_11.5.0/com.ibm.db2.luw.sql.ref.doc/doc/r0000910.html
(P.S. all the above assumes you are using Db2 LUW)
Try using SET SCHEMA to set the default schema to be used in the session:
SET SCHEMA SCHEMA_NAME;
SELECT * FROM TABLE_NAME;
When using DBeaver - right click on connection > Connection Settings > Initialization, and select your default DB and default Schema:
After that, open your SQL Script and select Active DB:
Whenever i have to execute sql commands in pgAdmin 4 i have to append schema_name with tables.
Eg :-
SELECT * FROM my_schema.users //where myschema is schema name
ORDER BY id ASC
Is there any way to execute sql commands in pgAdmin 4 without schema name, by setting a default schema in advance.
Some thing like this
SELECT * FROM programme
ORDER BY id ASC
- without specifying schema name with table.
Is there a way to set default schema in pgAdmin 4 for querying in sql tool?
You can do it in 2 ways:
SET search_path = my_schema, "$user", public; -- For current session only
ALTER ROLE your_role SET search_path = my_schema, "$user", public; -- Persistent, for role
You can also set it for whole database, same way as for role.
EDIT: Just to explain what this does - it will change where and in what order Postgres will search for objects matching object identifiers that did not get prefixed with schema name.
You might need also to restart pgAdmin4 in order for the search_path to start working. At least it was my case.
A good double check if the search_path was set in pgAdmin4 is to go to:
Login/Group Roles -> Right click on the user (by default it is 'postgres') -> Properties -> Parameters tab. Here you should see your new parameter 'search_path' with the value 'your_schema_name'.
All
I am trying to use dblink in PostgreSQL to run query on different databases. The following works if the table "user" is under the public schema:
select * from dblink(
'hostaddr=1.2.3.4 port=5434 dbname=dbname user=username password=password',
'select id from user')
as t1(
id bigint
);
However, I need to run the query on some other defined schemas. Does anyone know how to add the schema information in the above query? I can't figure it out from the PostgreSQL docs.
When you write SQL query like
SELECT id FROM user
PostgreSQL will resolve table name like user into fully qualified name like schema.tablename using schema search path, which by default is set to "$user",public.
In other words, user will resolve into public.user unless you tweaked server configuration.
However, you can specify schema explicitly in your statement, like this:
SELECT id FROM otherschema.user
I have installed oracle 10g express edition and I did not find the option to
create schema..
Is there a option to create schema in oracle 10g express edition
or else I have to install other oracle 10g..?
To create schema which oracle 10g
I have to install... what?
You don't need to explicitly create schema, Oracle automatically creates a schema when you create a user (see CREATE USER documentation).
If you really want, you can use CREATE SCHEMA statement and issue it through Oracle Express web interface or from SQL prompt.
The CREATE SCHEMA statement can include CREATE TABLE, CREATE VIEW, and GRANT statements. To issue a CREATE SCHEMA statement, you must have the privileges necessary to issue the included statements.
CREATE SCHEMA AUTHORIZATION oe
CREATE TABLE new_product
(color VARCHAR2(10) PRIMARY KEY, quantity NUMBER)
CREATE VIEW new_product_view
AS SELECT color, quantity FROM new_product WHERE color = 'RED'
GRANT select ON new_product_view TO hr;
As zendar said, creating a user automatically creates their schema (in Oracle these are pretty much the same concept).
When you create a Workspace in apex, it will ask you if you want to use an existing schema or create a new one - so that's another easy option you could use.