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
Related
I am looking to get all the update statements with old and new values within a database into one table.
For an example :
I have database name "users".
It contains four tables "primary_info","address_info","avtars","audit_logs"
Now, Whichever update statements executes on primary_info,address_info and avtars table that i need to log into audit logs table with below way.
ID, Table Name, Field_name,Old_value,New_value,Current Datetime
I know we can create triggers to manage such things.But i have database which contains more than 90 tables.So it won't help me to achieve by making trigger (update before) .
So is there any other way which i missed here ?
Thanks in advance.
I have MySQL tables that are all InnoDB.
We have so many copies of various databases spread across multiple servers (trust me we're talking hundreds here), and many of them are not being queried at all.
How can I get a list of the MAX(LastAccessDate) for example for all tables within a specific database? Esp. considering that they are InnoDB tables.
I would prefer knowing even where the "select" query was run, but would settle for "insert/update" as well, since, if a db hasn't changed in a long time, it's probably dead.
If you have a table that always gets values inserted you can add a trigger to the update/insert. Inside this trigger you can set the current timestamp in a dedicated database, including the name of the database from which the insert took place.
This way the only requirement of your database is that it supports triggers.
Alternatively you could take a look this link:
odify date and create date for a table can be retrieved from sys.tables catalog view. When any structural changes are made the modify date is updated. It can be queried as follows:
USE [SqlAndMe]
GO
SELECT [TableName] = name,
create_date,
modify_date
FROM sys.tables
WHERE name = 'TransactionHistoryArchive'
GO
sys.tables only shows modify date for structural changes. If we need to check when was the tables last updated or accessed, we can use dynamic management view sys.dm_db_index_usage_stats. This DMV returns counts of different types of index operations and last time the operation was performed.
It can be used as follows:
USE [SqlAndMe]
GO
SELECT [TableName] = OBJECT_NAME(object_id),
last_user_update, last_user_seek, last_user_scan, last_user_lookup
FROM sys.dm_db_index_usage_stats
WHERE database_id = DB_ID('SqlAndMe')
AND OBJECT_NAME(object_id) = 'TransactionHistoryArchive'
GO
last_user_update – provides time of last user update
last_user_* – provides time of last scan/seek/lookup
It is important to note that sys.dm_db_index_usage_stats counters are reset when SQL Server service is restarted.
Hope This Helps!
Is it possible to use any sort of logic in MySQL without using any procedures? My web hosting does not let me create any procedures so I'm looking for a workaround.
The type of thing I want to do is only add an item to a table if it doesn't already exist. Or add a column to a table if it's not already there. There are some operations that can be done such as CREATE TABLE IF NOT EXISTS and so on, but some operations I require do not have such luxuries :(
I realised late on that my lovely procs won't work and so I tried writing IF/ELSE logic as top-level queries, but for MySQL, IF ELSE blocks only seem to work inside functions/procs and not at the global scope.
Any workarounds greatfully received - I've already asked the hosting to grant me privileges to create procedures but no reply as yet...
I suppose you don't have access to the INFORMATION_SCHEMA either. You can possibly find solutions but it would be better, in my oninion, to:
Change your hosting provider. Seriously. Pay more - if needed - for a MySQL instance that you can configure to your needs. You only have a crippled DBMS if you are not allowed to create procedures and functions.
Posible workarounds for the specific task: You want to add a column if it doesn't exist.
1) Just ALTER TABLE and add the column. If it already exists, you'll get an error. You can catch that error, in your application.
2) (If you have no access to the INFORMATION_SCHEMA) maintain a version of the schema, for your database.
The best solution that I can think of would be to use an additional language with SQL. For example, you can run a query for a specific record, and based on the response that you get, you can conditionally run an INSERT statement.
For inserting a table if it doesn't exist, try using the SHOW TABLES statement and testing whether or not a name exists in the result set.
MySQL supports INSERT IGNORE. and INSERT ... ON DUPLICATE KEY UPDATE.
The following will insert a new row, but only if there is no existing row with id=10. (This assumes that id is defined as a unique or primary key).
INSERT IGNORE INTO my_table (id, col1, col2) values (10, "abc", "def");
The following will insert a new row, but if there is an existing row with id=10 (again, assuming id is unique or primary), the existing row will be updated to hold the new values, instead of inserting a new row.
INSERT INTO my_table (id, col1, col2) values (10, "abc", "def")
ON DUPLICATE KEY UPDATE col1=VALUES(col1), col2=VALUES(col2)
Also, CREATE TABLE supports the IF NOT EXISTS modifier. So you can do something like:
CREATE TABLE IF NOT EXISTS my_table ...
There are many other similar options and modifiers available in MySQL. Check the docs for more.
Originally I created a big script to create or update the database schema, to make it easier to deploy database changes from my local machine to the server.
My script was doing a lot of "if table 'abc' exists and it doesn't have a FK constraint called 'blah'" then create an FK constraint called 'blah' on table 'abc'... and so on.
I now realise it's not actually necessary to check whether a table has a certain column or constraint etc, because I can just maintain a schema-versioning system, and query the DB schema-version when my app starts, or when I navigate to a certain page.
e.g. let's say I want to add a new column to a table. It works like this:
Add a new migration script to the app code, containing the SQL required to add the column to the existing table
Increment the app's schema-version by 1
On app startup, the app queries the DB for the DB's schema-version
If DB schema-version < app schema-version, execute the SQL migration scripts between the two schema-versions, and then update the DB schema-version to be the same as the app
e.g. if the DB's schema-version is 5 and the app version is 8, the app will apply migration scripts 5-6, 6-7 and 7-8 to the DB. These can just be run without having to check anything on the DB side.
The app is therefore solely responsible for updating the DB schema and there's no need for me to ever have to execute schema change scripts on the local or remote DB.
I think it's a better system than the one I was trying to implement for my question.
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 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!