I do not know how to ask this question but my client asked me like this he wants for example he has a database at xxx.xxx.xxx.206 a table named Products but he also has a database at xxx.xxx.xxx.246and also a table called Products.
When he inserts a product at xxx.xxx.xxx.206 it should also be inserted inside Products table in xxx.xxx.xxx.246 automatically.
triggers came to my mind and I know how to make a trigger but... these kind of stuff he is asking is beyond my levels of knowledge using sql server.
How can I achieve such thing? Should I use triggers for this? but even using triggers how can I make that connection to another database?
Trigger can be a solution but when the destination is on another server it cause to reduce the performance.
I suggest you to create a job which transfer new inserted record to another server. Adding a new field is required to product table in xxx.xxx.xxx.206
Alter Table Products Add IsTransfered BIT Default(0)
I describe how to use this new filed in my answer to this question:
Identify new values in Table A and insert them in Table B
Related
We have a table in our Oracle Database that was created from an actual script.
Ex:
Create Table AS (Select * from table).
I was hoping to recover the original script the table was created from as the data is quite old in the table, but needs this created table needs to be refreshed. This table is created with data from another live table in our database, so if there is a way to refresh this without the original query - I'm open ears. Any solutions are welcomed!
Thanks!
I suppose you could also do a column by column comparison of this table against all others to see which one (if any) matches it. Of course, this would only be a guess.
It would require that object to actually be a materialized view instead of a table. Otherwise you are probably left off with exploring logs. Beyond that I doubt there is any way to recover the original select statement used to create that table.
I am working on a database used by separate applications. One of these applications is updating two fields in a table but I can't work out what one and don't have the source code for all the applications.
I am wondering if it is possible to write a log (to another table or elsewhere) to what the last update statement made against the table in question was. E.g. to record all SQL that has attempted to update the table automatically...
create a trigger before update on this table. Also create a new table. In that trigger store values before and after update in to a newly created table
I don't have much knowledge in TRIGGERS, below is my doubt kindly suggest any answers.
SYSTEM:
I have a table called A with Triggers, it designed in such a way if any update/insert happens it will update/insert the same in Table B.
PROCESS:
Table A will get updated by multiple users
MY QUESTION:
I want to block one user/Batch JOB. i.e. if any update/insert is performed by this user/BatchJob in TABLE A, it wont be propagated to Table B.
IS it possible in DB2 Triggers? If so Please Help me. Thanks in Advance!
You could add a new table to your DB that contains users you want to block (or add a column to an existing user table).
Then change your trigger like this
if current_user is not in blocked_user_table
then
insert in table b
end
One third party app is storing data in a huge database (SQL Server 2000/2005). This database has more than 80 tables. How would I come to know that how many tables are affected when application stores a new record in database? Is there something available I can retrieve the list of tables affected?
You might be able to tell by running a trace in SQL Profiler on the database - the SQL:StmtCompleted event is probably the one to monitor - i.e. if the application does a series of inserts into multiple tables, you should see them go through in Profiler.
You can use SQL Profiler to trace SQL queries. So you will see sequence of calls caused by one button click in your application.
Also use can use metadata or SQL tools to get list of triggers which could make a lot of actions on simple insert.
If you have the SQL script that used to store the new record(Usually, it should be insert statement, or other DML statement such as update, merge and so on). Then you may know how many tables were affected by parsing those SQL script.
Take this SQL for example:
Insert into emp(fname, lname)
Values('john', 'reyes')
You can get result like this:
sstinsert
emp(tetInsert)
Tables:
emp
Fields:
emp.fname
emp.lname
you can add triggers on tables that get fired on update - you could use this to update a log table that would report what was being updated.
see more here: http://www.devarticles.com/c/a/SQL-Server/Using-Triggers-In-MS-SQL-Server/
Profiler is the way to go, as others have said especially with an unfamilar third party database.
I would also spend some time creating diagrams so you can see the foreign key relationships and understand how the database is put together. I usaully know my database structure so well, I can tell from the fields being inserted what tables they affect and I know what triggers are on my tables and what they affect. There is no substitute for taking the time to understand the database you support.
I have written the following trigger in SQL server:
create trigger test_trigger
on invoice -- This is the invoice table
for insert
as
declare #invoiceAmount int -- This is the amount specified in the invoice
declare #custNumber int -- This is the customer's id
--use the 'inserted' keyword to access the values inserted into the invoice table
select #invoiceAmount = Inv_Amt from inserted
select #custNumber = cust_num from inserted
update customer
set amount = #invoiceAmount
where Id = #custNumber
Will this be able to run in MS Access or is the syntax different?
The Access database engine (formerly called Jet) does not have triggers and regardless has no control-of-flow syntax e.g. a PROCEDURE must consist of exactly one SQL statement.
Tell us what you really want to do and there could be an alternative syntax.
For example, you could create a new key using a UNIQUE constraint on invoice, (cust_num, Inv_Amt), a FOREIGN KEY customer (id, amount) to reference the new key, a VIEW that joins the two tables on the FOREIGN KEY columns and exposing all four columns, then INSERT into the VIEW rather than the table 'invoice'; you may want to use privileges to prevent INSERTs to the base table but user level security was removed from the new Access 2007 engine (called ACE).
But, if you don’t mind me saying, I think your trigger doesn't reflect a real life scenario. A column vaguely named 'amount' in table 'customer' to hold the most recent invoice amount? What about when the inserted logical table contains rows for more than one customer? As I say, I think you need to tell us what you are really trying to achieve.
Access doesn't have triggers
Your trigger that you show here will bomb out since it does not take into account multirow updates the moment someone updates more than one row (and don't say it won't happen because it will better to practice some defensive coding)
Triggers fire per batch not per row, please read Multirow Considerations for DML Triggers
join inserted pseudo table and the invoice table instead to update the values...that works for 1 and more than 1 row
They may be coming in Access 2010? http://blogs.msdn.com/access/archive/2009/08/13/access-2010-data-macros-similar-to-triggers.aspx
MS Access doesn't have triggers.
That is, the the Access Jet engine (which creates .mdb files). If Access is connecting to a database server, then it will use whatever triggers are in that database.
I've never come across triggers in Access unless it's dealing with ADP on SQL Server. So your answer is yes, it's the same if you're on SQL Server for the backend, and no if the table is stored in Access.