I have several bases on multiple servers with tables in the same column pattern.
What I need to do is create a trigger in the database to audit delete, update, insert is there any way I can dynamically leave the table name that was given update?
There is more than one table in each database to be monitored.
Every help is welcome
You can check with this answer this might help you. Here I have given idea to create a trigger to monitor the update value in table.
https://stackoverflow.com/a/54229188/10532500
The output is as shown below of the trigger in the form of an audit table.
Related
I am currently working in a SQL server database where I have a table User that has a schema like so:
username
category
user1
gaming
user2
gaming
user3
sports
My summary table UserCategoryCount is a simple groupby statement for how many users belong to each category and looks like this:
category
numUsers
gaming
2
sports
1
New entries are constantly being uploaded to the User, and I want to be able to stream updates in the User table to the UserCategoryCount summary table. I am aware that I can create a simple VIEW statement that performs a groupby on the User table, but I would like UserCategoryCount to be its own table that automatically changes based on new users being uploaded to the User table.
My first thought was to create a trigger that will detect when the User table has been updated. So far, the most simple but cheesy solution I can think of is creating a trigger that simply deletes and refreshes UserCategoryCount:
CREATE TRIGGER TRG_Add_User
ON User
AS
BEGIN
DELETE FROM UserCategoryCount
INSERT INTO UserCategoryCount (category, numUsers)
SELECT Category, Count(Category) as numUsers
FROM User GROUP BY Category
END
GO
But this seems like a really hacky way of updating the UserCategoryCount table. Any help on how to improve this update statement so that I don't have to completely overwrite the table every time a new user or batch of users has been inserted would be greatly appreciated.
For a start, your trigger is seriously flawed: it does not use the inserted or deleted tables and instead recalculates the whole thing every time, this is going to be very bad for performance. It also does not specify whether it is for inserts, updates or deletes.
A much better solution is to use an indexed view. This is like a regular view, except that the server maintains the actual data on disk, and updates it in real-time whenever there are changes to the underlying tables.
CREATE OR ALTER VIEW dbo.UserCategoryCount
WITH SCHEMABINDING
AS
SELECT
u.Category,
COUNT_BIG(*) AS numUsers
FROM dbo.User u
GROUP BY u.Category;
GO
CREATE UNIQUE CLUSTERED INDEX CX_UserCategoryCount ON dbo.UserCategoryCount (Category);
There are some restrictions on indexed views, among them:
They must be schema-bound, and therefore underlying columns cannot be changed
All tables must be two-part, schema and table
Only joins allowed are INNER or CROSS, no LEFT/RIGHT/FULL/APPLY or derived tables, CTEs or subqueries.
If there is a GROUP BY, you must add COUNT_BIG, and the only other aggregate allowed is SUM
I have a table COMPANY where companies are kept. I want to create a view of that table, let's name it COMPANY_CDC but with one caveat:
When an entry in the original table is deleted, I want to set a deleted flag on the view entry instead of deleting it.
EDIT Why soft deletes? The point is that im performing change data capture using JDBC, and JDBC is only able to capture soft deletes. Inserts / updates are no problem.
If this cannot be done by using a view, what would be an alternative solution?
You can insert deleted values in another table using trigger
, and with join of these two table you can create your view.
I have seen something like this asked a number of times but not quite in this configuration. I have a table that has a one to many relation.
Let’s say I have a computer table and a parts table. The user enters a generic info in the computer table then selects parts that are stored in the parts table with a relationship to the computer table of computerId. So the original write is a simple insert. Now let’s say the user select the computer again and changes the part on the pc, adds some new, removes some, and updates a few. Then the user hits save to save the changes. I run a simple update on the computer table but now the issue with the parts table.
Would it be better to delete all the records from the parts table for the computer Id and then do a clean insert of all the parts selected.
Or Run some method that would look at the existing parts in the table and where the part has been updated update the record, where the part no longer exists do a delete, and then insert the remaining parts?
Clearly the simple solution is to delete all and then insert all.
The down side of this SQL traffic, locks, and table fragmentation.
If it is small table and only few concurrent users then fine.
In a high volume environment I do the following
There is no update - that is just an ignore
- delete items gone
- ignore any items not changed
- insert new items
And you can do that in one pass two/three statements.
Or you could define a stored procedure.
Do the delete before the insert to clear space first.
You can get real fancy and use an update for delete / insert but that just gets more complex than it is worth in my mind. You would still have an insert or a delete if the item count is not the same.
delete comp_part
where compID = #compID and partID not in (....);
Insert is a little more tricky:
You can to it with a series of inserts and if you have a PK just let the insert fail
The other way is to create a #table and use it for both the delete and insert
This is only worth the hassle if you have a REALLY busy table.
It all depends upon the business model, if you would want to track the transaction than its not a good option to delete it. If you have all your old transactions with your customers than it would be beneficial for tracking purposes., Your CustomerID would be Primarykey and you can have another Unique key as PartOrderID which will be a unique value for each insert.
Hope this helps
Really you should have three tables. Product, Part, and ProductPart; the ProductPart table would store the association of "this product has these parts". As far as updating, the simplest thing would be to delete all ProductParts for a given Product and re-insert the records you want.
I need to track user making inserts and updates on Sybase table.
What is the best way of achieving this?
Please use trigger to track all the inserts and updates. For every action store/update USER name in a particular column say, modifier.
I have requirement like, suppose I have a 'property' table which has 'ListingKey' field and I want to do entry in another table say 'property_history' table whenever 'ListingKey' field is update. How it is possible with mysql ? should I use trigger then how can I use it?
Please Help me,
Thanks,
:Jimit
By using trigger you can easily achieve this
following is link for the my sql trigger creation
http://dev.mysql.com/doc/refman/5.0/en/create-trigger.html