I need to create public synonyms for sequence.Could you please suggest how to create synonyms for sequence in oracle 11g.
Alter script to add constraint:
ALTER TABLE schema.table_name ADD( CONSTRAINT pk PRIMARY KEY(primaryKey_ID));
Sequence:
CREATE SEQUENCE table_name START WITH 1;
According to documentation you can create a public synonym for your sequence in the same way you do for a table:
create public synonym table_name for yourSchema.table_name;
create public synonym sequence_name for yourSchema.sequence_name;
Related
I have 848 NONEDITIONABLE PUBLIC SYNONYM that have the TABLE_OWNER as Dev.
I want help to alter all these NONEDITIONABLE PUBLIC SYNONYM to Prod, but in order to do so we need to extract all the queries. Is there a query to do so?
current:
CREATE OR REPLACE NONEDITIONABLE PUBLIC SYNONYM "CONFIG_SEQ" FOR "Dev"."CONFIG_SEQ";
expected:
CREATE OR REPLACE NONEDITIONABLE PUBLIC SYNONYM "CONFIG_SEQ" FOR "Prod"."CONFIG_SEQ";
your time and help is appreciated.
Thank You
we need to extract all the queries. Is there a query to do so?
Yes. Generate the script from the data dictionary:
select 'CREATE OR REPLACE NONEDITIONABLE PUBLIC SYNONYM "'
|| synonym_name ||'" FOR "PROD"."' || table_name || '";'
from all_synonyms
where owner = 'PUBLIC'
and table_owner = 'DEV'
/
For future reference please remember that needing to do this is a failure of process. DDL scripts are just like any other code, and should be kept in a source control repository, and checked out and deployed through managed releases.
I am using SQL*Plus to create a table with the following sql:
CREATE TABLE SCHEMA_OWNER.TEST_TABLE (
ID NUMBER(19,0) NOT NULL,
TEST_STRING VARCHAR2(255 CHAR),
PRIMARY KEY (ID)
);
When I try and do an insert with any user into that table, I see the following error:
INSERT INTO TEST_TABLE (ID, TEST_STRING) values (1, 'Test')
ORA-01950: no privileges on tablespace 'USERS'
This implies that the table has been created in the Users tablespace, but when I look in the USER_TABLES table, I see that the tablespace is the same as all of the other tables, and not 'Users':
SELECT table_name, tablespace_name from USER_TABLES;
TABLE_NAME TABLESPACE_NAME
---------------- ---------------
TABLE1 DATA_TABLESPACE
TEST_TABLE DATA_TABLESPACE
When I create the table in SQL developer using the same SQL, I don't have any errors when inserting data.
1) Why am I getting this error when the table isn't in the Users tablespace?
2) Why am I only getting it when running the sql script from SQL*Plus?
Thanks to Aleksej for suggesting it could be an issue with the indexes. The problem was that when I was creating the index on the table, I wasn't creating it for the schema owner, which meant that it was being created in a different tablespace.
So instead of
CREATE INDEX TEST_TABLE_IDX ON SCHEMA_OWNER.TEST_TABLE(TEST_STRING);
I needed to do
CREATE INDEX SCHEMA_OWNER.TEST_TABLE_IDX ON SCHEMA_OWNER.TEST_TABLE(TEST_STRING);
Is there some equivalent to the Mysql specific instruction that disable the check of the foreign keys constraints ?
SET FOREIGN_KEY_CHECKS = 0;
There is no command in Oracle that will disable all constraints at once.
However it seems you want to disable constraints in the context of dropping tables. In that case you can use the CASCADE CONSTRAINTS clause to drop the referencing constraints from other tables along with the table being dropped.
Here's an example:
SQL> CREATE TABLE t1 (ID NUMBER PRIMARY KEY);
Table created
SQL> CREATE TABLE t2 (ID NUMBER REFERENCES t1);
Table created
SQL> INSERT INTO t1 VALUES (1);
1 row inserted
SQL> INSERT INTO t2 VALUES (1);
1 row inserted
SQL> -- this fails because of the foreign key
SQL> DROP TABLE t1;
ORA-02449: unique/primary keys in table referenced by foreign keys
SQL> DROP TABLE t1 CASCADE CONSTRAINTS;
Table dropped
SET FOREIGN_KEY_CHECKS = 0; is session based. In an Oracle context I can only imagine you needing to do this when you have circular references.
You've commented that this is what you want to do:
SET FOREIGN_KEY_CHECKS = 0;
DROP TABLE table1;
DROP TABLE table2;
SET FOREIGN_KEY_CHECKS = 1;
I'm assuming that this means that TABLE1 has a foreign key referencing TABLE2 and TABLE2 has a foreign key referencing TABLE1.
If this is the case then Moudiz's answer is correct. You want to disable the foreign keys before dropping the table:
alter table table1 disable constraint <constraint_name>;
alter table table2 disable constraint <constraint_name>;
drop table table1;
drop table table2;
There's no point disabling all foreign keys for the length of the session, you're only interested in two of them, both of which will be dropped with the table.
You don't want to ever disable all foreign keys.
The only other context I can think of this in is if you want to insert something into your circular reference, in which case you would declare the constraint as DEFERRABLE. This means that the constraint check is done at the end of the transaction rather than on DML being performed, see the documentation.
If your references aren't circular then simply drop the tables in the other order.
IF Your asking for a query to disable a foreign key then try this :
ALTER TABLE mytable
disable CONSTRAINT fk_mytable;
I was reading this article:
Managing Oracle Synonyms
Regarding the order of preference, when it come to resolving an object name to the actual object, it says:
Local objects will always be accessed first.
If a local object does not exist, the object with a private synonym will be accessed.
If a private synonym does not exist or the object does not exist, then the public synonym will be used.
I was wondering if the public objects are missing in this order somehow?
E.g. if user BOB queries
select * from FOOBAR
and there is no BOB.FOOBAR in dba_tables/views but PUBLIC.FOOBAR.
Does Oracle resolve it to PUBLIC.FOOBAR or will it check for synonyms first?
Thank you.
In your example, FOOBAR is almost certainly a public synonym. There is no PUBLIC schema but PUBLIC is listed as the owner of a public synonym.
If I create a new public synonym
SQL> create public synonym pub_syn_emp
2 for scott.emp;
Synonym created.
the owner of that synonym ends up being PUBLIC
SQL> ed
Wrote file afiedt.buf
1 select object_name, owner, object_type
2 from dba_objects
3* where object_name = 'PUB_SYN_EMP'
SQL> /
OBJECT_NAME OWNER OBJECT_TYP
-------------------- ---------- ----------
PUB_SYN_EMP PUBLIC SYNONYM
In addition, item #3 does not appear to be correct. If there is a private synonym that points to a non-existent object and a public synonym that points to a valid object, the private synonym still takes precedence. You'll just get an error when Oracle tries to resolve the private synonym to an actual object.
SQL> create synonym syn_emp for scott.no_such_table;
Synonym created.
SQL> create public synonym syn_emp for scott.emp;
Synonym created.
SQL> select * from syn_emp;
select * from syn_emp
*
ERROR at line 1:
ORA-00980: synonym translation is no longer valid
At least up to 10g, PUBLIC is not a real user. You cannot create objects in the "Public schema":
SQL> CREATE TABLE public.foobar (id integer);
CREATE TABLE public.foobar (id integer)
ORA-00903: invalid table name
SQL> CREATE TABLE system.foobar (id integer);
Table created
SQL>
If you run this query:
SELECT object_name
FROM dba_objects
WHERE owner='PUBLIC'
AND object_type IN ('TABLE', 'VIEW');
You can answer the question about pre-defined tables/views in the PUBLIC "schema".
I create a table in Oracle 11g with the default value for one of the columns. Syntax is:
create table xyz(emp number,ename varchar2(100),salary number default 0);
This created successfully. For some reasons I need to create another table with same old table structure and data. So I created a new table with name abc as
create table abc as select * from xyz.
Here "abc" created successfully with same structure and data as old table xyz. But for the column "salary" in old table "xyz" default value was set to "0". But in the newly created table "abc" the default value is not set.
This is all in Oracle 11g. Please tell me the reason why the default value was not set and how we can set this using select statement.
You can specify the constraints and defaults in a CREATE TABLE AS SELECT, but the syntax is as follows
create table t1 (id number default 1 not null);
insert into t1 (id) values (2);
create table t2 (id default 1 not null)
as select * from t1;
That is, it won't inherit the constraints from the source table/select. Only the data type (length/precision/scale) is determined by the select.
The reason is that CTAS (Create table as select) does not copy any metadata from the source to the target table, namely
no primary key
no foreign keys
no grants
no indexes
...
To achieve what you want, I'd either
use dbms_metadata.get_ddl to get the complete table structure, replace the table name with the new name, execute this statement, and do an INSERT afterward to copy the data
or keep using CTAS, extract the not null constraints for the source table from user_constraints and add them to the target table afterwards
You will need to alter table abc modify (salary default 0);
new table inherits only "not null" constraint and no other constraint.
Thus you can alter the table after creating it with "create table as" command
or you can define all constraint that you need by following the
create table t1 (id number default 1 not null);
insert into t1 (id) values (2);
create table t2 as select * from t1;
This will create table t2 with not null constraint.
But for some other constraint except "not null" you should use the following syntax
create table t1 (id number default 1 unique);
insert into t1 (id) values (2);
create table t2 (id default 1 unique)
as select * from t1;