I want to replicate table A data to B as we have some different columns in table B. So It is possible to replicate data.
Schema names are different also
example:
table A
(custome_name, customer_desc,create_date,create_user,update_date,update_user)
table B
(customer_id,custome_name, customer_desc,create_date,create_user,update_date,update_user)
User B has to grant privileges to user A so that A could insert data into their table:
grant insert on table_b to a;
Then, user A would write an INSERT statement, specifying which columns in user B's table_b will be populated with which column values from table_a
INSERT INTO b.table_b (custome_name,
customer_desc,
create_date,
create_user,
update_date,
update_user)
SELECT custome_name,
customer_desc,
create_date,
create_user,
update_date,
update_user
FROM table_a;
That's it.
If users reside in different databases, you'd use a database link.
Related
Is there a way to give a PostgreSQL user access to a different columns on different rows of a table? For example in the following table, is there some combination of GRANT or POLICY or ??? that would only allow the user to view the "allowed" cells?
CREATE TABLE my_table (
id INT,
col_a TEXT,
col_b TEXT
);
INSERT INTO my_table VALUES
(1, 'allowed', 'allowed'),
(2, 'allowed', 'forbidden')
;
I think it can be done by splitting the columns in to different tables, but is it possible with only a single table?
One possible solution suggested by O. Jones - use a view:
CREATE OR REPLACE VIEW my_secure_view AS
SELECT
id,
col_a,
CASE WHEN id = 1 THEN col_b ELSE NULL END AS col_b
FROM my_table;
GRANT SELECT ON my_secure_view TO whatever_user;
REVOKE SELECT ON my_table FROM whatever_user;
Is there a better way?
You can do this by creating a VIEW containing the rows and columns you allow your user to see, then granting the user SELECT access to the view but not the underlying table.
For example
CREATE OR REPLACE VIEW my_secure_view AS
SELECT allowedcol1, allowedcol2
FROM my_table
WHERE col_b <> 'forbidden';
GRANT SELECT ON my_secure_view TO whatever_user;
REVOKE SELECT ON my_table TO whatever_user;
You can also, if you wish, write stored procedures and grant access to them to the users you choose, while revoking access to the underlying tables.
I have 4 tables:
Table A:
LogID (unique identifier),
UserID (bigint),
LogDate (date/time),
LogEventID (int),
IPID (varchar(36)),
UserAgentID (varchar(36))
Table B:
IPID (unique identifier),
IPAddress (varchar(255))
Table C:
UserAgentID (unique identifier),
UserAgent (varchar(255))
Table D:
LogEventID (int),
LogEvent (varchar(255))
I am trying to write the to Table A but need to check Table B, Table C and Table D contain data so I can link them. If they don’t contain any data, I would need to create some. Some of the tables may contain data, sometimes none of them may.
Pretty much everything, really struggling
first, you do a insert into table B, C, D WHERE NOT EXISTS
example
INSERT INTO TableB (IPID, IPAddress)
SELECT #IPPD, #IPAddress
WHERE NOT EXISTS
(
SELECT *
FROM TableB x
WHERE x.IPID = #IPID
)
then you insert into table A
INSERT INTO TableA ( . . . )
SELECT . . .
SQL Server doesn't let you modify multiple tables in a single statement, so you cannot do this with a single statement.
What can you do?
You can wrap the multiple statements in a single transaction, if your goal is to modify the database only once.
You can write the multiple statements in stored procedure.
What you really probably want is a view with insert triggers on the view. You can define a view that is the join of the tables with the values from the reference tables. An insert trigger can then check if the values exist and replace them with the appropriate ids. Or, insert into the appropriate table.
The third option does exactly what you want. I find that it is a bit of trouble to maintain triggers, so for an application, I would prefer wrapping the logic in a stored procedure.
I want to insert a new row in my table.
There I want to put the ID with the help of seq_name.nextval.
So how to know the sequence name for that particular table?
To use a sequence to generate IDs, you create it normally in the schema where the table is.
As user application user GEM_APP:
CREATE TABLE my_table (id NUMBER, col1 ...);
CREATE SEQUENCE my_seq;
The application user itself (and f.i. it's stored procedures) can use the sequence directly:
INSERT INTO my_table (id, col1) VALUES (my_seq.nextval, 'bla');
However, other users need the correct privileges. Usually, you grant select rights on the sequence to the same users or roles you grant insert rights on the table:
GRANT SELECT, INSERT ON my_table TO user_xy;
GRANT SELECT ON my_seq TO user_xy;
Then the other user can insert data into the table, but must qualify the schema:
INSERT INTO gem_app.my_table(id, col1) VALUES (gem_app.my_seq.nextval, 'bla');
You can create aliases to hide the schemas, some people like them, some not, but I would definitely not recommend to use PUBLIC synonyms as they are hard to control and create all kind of namespace clashes.
In Table A i have many fields like referenceid, amount, timestamp, remarks, status, balancebefore, balanceafter, frmsisdn, tomsisdn, id etc etc
I want to create a new table, Table B based of Table A(with column names, datatypes etc etc) but i only need specific columns that are in table A.
I tried select * into TableB from TableA where 1 = 2 but it says ORA-00905: missing keyword. I am using TOAD.
thank you
In Oracle, the correct syntax is create table as. SELECT INTO is used primarily in SQL Server and Sybase.
create table tableb as
select . . .
from tableA;
Only include the where clause if you don't actually want to insert any rows.
In MySQL the syntax is the same as Oracle's (see here).
Notice that the new table does not contain any constraints from the original table (indexes, keys, etc.)
I have 3 tables in SQL server with following fields.
Table 1- id, name, age.
Table 2- id,email, Address.
Table 3- id, name, email.
I wish to use two triggers like, when I insert values on Table 1, id and name should insert in Table 3. When I insert values in Table 2, Email should insert in Table 3 and it should insert at id and name position means it should not show NULL values. Name,id and email should insert in one row.
You should make the View for inserting data from two tables to a single table
You should fix the data model so that it is normalized. You wouldn't need a trigger to replicate data into Table 3 if the name and email columns weren't in 2 tables.