I have a table which get new data inserted every minute or so. According to the source code I have here, it is only done in one class which is not used anymore.
Is there any way to trace the inserts? What I mean is to see which queries they were inserted by, who sent those queries etc. As much info as possible.
I have tried several ways myself (e.g.sp_who2 'Active' stored procedure) without any success. I also have access to the machine running the SQL server and to the transaction backup files (.trn files) but have no idea how to open those files.
Add trigger to the table which follows inserts and insert to other table these variables:
getdate(),
host_name(),
App_Name(),
suser_sname()
Seems to me that this is enough
The trigger looks like this:
CREATE TRIGGER YourTrigger On YourTable
AFTER INSERT
AS
SET NOCOUNT ON;
INSERT logtable
SELECT APP_NAME(), HOST_NAME(), SUSER_SNAME(), GETDATE(), * FROM INSERTED
GO
OR
you can use Sql Server Profiler for catching the queries - it may be more flexible
You may use sp_depends like this:
sp_depends tablename
This only states information in the same database but it might say what you need!
Related
Sorry for asking this question, but I am a beginner in SQL, my colleague at work build a view, which I need as datasource for a report, however since this view is based on several other views it takes like 45 minutes to execute the query. This is way to long. Therefore I created a table from that view, initial execution time is the same, but once in place it executes in seconds.
In Microsoft SQL Server 2014 I used the following query:
select *
into [dbo].[MAT_v_demnew_daily_am_all_data]
from [dbo].[v_demnew_daily_am]
This works fine, but since the view is updated daily I also need to refresh the table everyday. When I now execute the above mentioned query I get the message that the table already exists.
That's why I tried to use 'insert' in this case:
insert into [dbo].[MAT_v_demnew_daily_am_all_data]
select *
from [dbo].[v_demnew_daily_am]
Here I have the problem that it not only inserts the additional data but also the already existing data, so in the end I have duplicates.
As a workaround I now manually delete the [dbo].MAT_v_demnew_daily_am_all_data] table and then execute the select * into query.
Now I am looking for an easier solution, is it possible to having the table deleted by query and in the same query create a new one by select * into or is it possible to only insert new data from the view to the table so that I don't get duplicates.
Moreover, is it possible to have such SQL statement being executed automatically on a daily basis, maybe by .bat file and windows task scheduler?
I know that the source of all problems is the View and that we should improve that, but looking for a short term solution first.
Thanks so much.
Mathias
Try this:
IF OBJECT_ID('dbo.MAT_v_demnew_daily_am_all_data', 'U') IS NOT NULL
DROP TABLE dbo.MAT_v_demnew_daily_am_all_data
SELECT INTO dbo.MAT_v_demnew_daily_am_all_data FROM dbo.v_demnew_daily_am
This query is reusable on a daily basis.
You can create one stored procedure including this query.
Then you only need to execute the stored procedure.
Updated
Before you create the stored procedure, please check if you have the permission.
Then try:
create procedure [procedure_name]
as
IF OBJECT_ID('dbo.MAT_v_demnew_daily_am_all_data', 'U') IS NOT NULL
DROP TABLE dbo.MAT_v_demnew_daily_am_all_data
SELECT INTO dbo.MAT_v_demnew_daily_am_all_data FROM dbo.v_demnew_daily_am;
After you create it:
EXEC [procedure_name];
I want to replicate certain table from one database into another database in the same server. This tables contain exactly the same fields.
I was considering to use MySQL Replication to replicate that table but some people said that it will increase IO so i find another way to create 3 Trigger (Insert, update and Delete) that will perform exactly the same thing like what i expect.
My Question is, which way is better? Is it using MySQL replication is better even though it's in the same server or using Trigger to replicate the data is better.
Thanks.
I don't know what is your goal, but I got mine getting use of the VIEW functionality.
I had two different applications with separate databases but in the same Mysql server. Application2 needed to get a few data from Application1. In general, this is a trivial situation that you can handle with USE DB1; or USE DB2; as your needing, but my programming framework does not work very well with multiple DBs.
So, lets see my solution...
Here is my select query to retrieve this data:
SELECT id, name FROM DB1.customers;
So, using DB2 as default schema, I've created a VIEW:
USE DB2;
CREATE VIEW app1_customers AS SELECT id, name FROM DB1.customers;
Now I can retrieve this data in DB2 as a regular table with a regular SELECT statement.
SELECT * FROM DB2.app1_customers;
Hope ts useful. BR
Assuming you have two databases on the same server i.e DB1 and DB2 and the table is called tbl1 and it is sitting in DB1 you can query the table like this:
USE DB1;
SELECT * FROM tbl1;
USE DB2;
SELECT * FROM DB1.tbl1;
This way you wont need to copy the data and worry about extra space and extra code. You can query a table in another database on the same server. Replication and triggers are not your answer here. You could also create a view to encapsulate the SQL statement.
Definitely triggers is the way to go. Having another server (slave) will need to spare several MB for installation, logs, cpu and memory usage.
I'd use triggers to keep both tables equal. If you want to create a table with the same columns definition and data use:
USE db2;
CREATE TABLE t1 AS SELECT * FROM db1.t1;
After that, go ahead and create the triggers for Update, Insert and Delete statemetns.
Also you could ALTER the new table to a different engine like MEMORY or add indexes to see if you can improve something.
I need to log all events on all tables in table database_log (id, user, timestamp, tablename, old_value, new_value).
I thought I can create the same trigger on all tables (~25) with a little php script dynamically replace the name's table. But in this case I can retrieve the old and new value, because all tables haven't the same columns so I can't just concat all field for store in the "old_value" and "new_value" (even if I retrieve fields in schema because I can't use a concat() on it for select all value and store in variable).
For exemple a :
SELECT * into v_myvar FROM my_table where id=OLD.id;
CALL addLog(v_myvar)
Where addLog is procedure taking my old value and add a line with other informations, could save my life.
So, I'm looking for a sexy solution with one trigger and/or one procedure (by table) or a useful tool. Someone have a solution ?
Thanks
SET GLOBAL general_log_file = '/var/log/mysql/mysql.log';
The general query log is a general record of what mysqld is doing. The server writes information to this log when clients connect or disconnect, and it logs each SQL statement received from clients.
See the MySql Documentation
Using a MySQL DB, I am having trouble with a stored procedure and event timer that I created.
I made an empty table that gets populated with data from another via SELECT INTO.
Prior to populating, I TRUNCATE the current data. It's used to track only log entries that occur within 2 months from the current date.
This turns a 350k+ log table into about 750 which really speeds up reporting queries.
The problem is that if a client sends a query precisely between the TRUNCATE statement and the SELECT INTO statement (which has a high probability considering the EVENT is set to run every 1 minute), the query returns no rows...
I have looked into locking a read on the table while this PROCEDURE is ran, but locks are not allowed in STORED PROCEDURES.
Can anyone come up with a workaround that (preferably) doesn't require a remodel?
I really need to be pointed in the right direction here.
Thanks,
Max
I'd suggest an alternate approach instead of truncating the table, and then selecting into it...
You can instead select your new data set into a new table. Next, using a single RENAME command, rename the new table to the existing table and the existing table to some backup name.
RENAME TABLE existing_table TO backup_table, new_table TO existing_table;
This is a single, atomic operation... so it wouldn't be possible for the client to read from the data after it is emptied but before it is re-populated.
Alternately, you could change your TRUNCATE to a DELETE FROM, and then wrap this in a transaction along with the SELECT INTO:
START TRANSACTION
DELETE FROM YourTable;
SELECT INTO YourTable...;
COMMIT
I know that triggers can be used on insert, update and delete, but what about a trigger (or sort of) on a select statement. I want to use a trigger to insert data on a table B when it is selected an existent record on a table A, it could be possible?.
Thanks in advance.
You should design your application so that database access occurs only through certain methods, and in those methods, add the monitoring you need.
Not exactly a trigger, but you can:
CREATE FUNCTION myFunc(...) BEGIN INSERT INTO myTable VALUES(...) END;
And then
SELECT myFunc(...), ... FROM otherTable WHERE id = 1;
Not an elegant solution, though.
It is not possible in the database itself.
However there are monitoring/instrumentation products for databases (e.g. for Sybase - not sure about MySQL) which track every query executed by the server, and can do anything based on that - usually store the query log into a data warehouse for later analysis, but they can just as well insert a record into table B for you, I would guess.
You can write an application which will be monitoring the query log and doing something when a select occurs. A pretty crude way to solve the problem though...