SQL Server Admin 2014 :: Transaction Log And TempDB Calculations
Mar 13, 2014
Is there a formula for calculating how expensive a transaction will be in terms of disk space used before its run. I dont want it accurate to the MB, but rough enough so I can determine how much additional space to assign to a transaction log or SAN volume.
Currently we're reindexing ~25billion rows, nothing too wide, say 12 columns consisting of 1 varchar(50) and the rest ints, bits and money.Roughly speaking if I reindex the clustered index on an int indetity, (with sort_in_tempdb) how would I calculate the the disk space used?
Message: Executed as user: NT AUTHORITYSYSTEM. The transaction log for database 'tempdb' is full. To find out why space in the log cannot be reused, see the log_reuse_wait_desc column in sys.databases [SQLSTATE 42000] (Error 9002). The step failed in my sql server agent job i have the above error, this type of errors i got some of multiple jobs.
I have Full database backup upto previous day and transaction logfile of Today transaction. my database has crashed. I have restored previous day's Full backup. I have faced difficulty to restore today's transaction from today's transaction log. What are the steps to restore full database back and one day's transaction log file. Note: there is no differential database backup and transaction backup.
I have a database that is part of AlwaysOn that is filling up the transaction log drive even though I have a daily full backup and transaction logs set for every 2 hours. The backups are going from both the primary and secondary replica backuping up to the shared disk and I have the backup preferences set to the primary.
When I try to shrink the log I get 'The transaction log for database 'DB' is full due to 'LOG_BACKUP''. I have to manually backup the trans log and then shrink, why the maintenance plan backups aren't doing this even though they are "working".
We have multiple databases on a single instance in an OLTP environment. I have my data files on a separate SAN LUN from my transaction log files (and a few NDFs split out onto additional LUNs). I was wondering if there is a performance benefit to putting each LDF file on its own LUN? Or at least my few busiest LDFs?
We are currently on 2012, but I'm having to put together specs for a 2014 installation and need to answer this question without having an environment in which I can benchmark different setups. I just want to hear whether or not others have done this (why or why not?).
I'm working on a large scale project that is currently in production. We have a big process that recently changed to use In-Memory Tables with SQL 2014 for performance efficiency.
The Process uses:
51 In-Memory SQL Tables. 50 Stored Procedures (not native) that loads data(Insert) from about 150 regular Tables and IM tables. 300 Validations (short stored procedure not native) Selecting from those 50 In-Memory Tables (And insert to In-Memory table that save the validation errors if exists on In-Memory table).
At the end of this process we clean the table from the data that relavnt to etch prosses(DELETE FROM WHERE)
B.T.W No UPDATE STAT on In-Memory are used-when we test the prosses it slow as down and cause some locks.
We are calling this process from ADO.Net, loads stored procedure first and then validations, each SP use different SQL Connection. In normal use, everything works fine and takes about 1.5 second.
Under stress test (6 Clients X 100 Tasks) for 30 minutes. After several minutes we are starting to get this SQL Exception (1 SQL Exception for every 20 tasks):
41301. A previous transaction that the current transaction took a dependency on has aborted, and the current transaction can no longer commit.
Transactions in Memory-Optimized Tables
The Exception is not clear. We are not using BEGIN TRANSACTION in the process. The SQL Exception occurs in different stored procedures each time.
I proposed on a new server that we separate Data Files, Log Files, tempDB, Backups, etc. onto separate LUNS on a SAN with High Speed Solid State Drives.I was told that with the new technology with solid state SAN's that it would decrease performance and that it did not work the same way as it did when you had RAID 5's etc.I thought that if things were cared out correctly by a SAN Administrator they would know how to configure for optimal performance.
I've recently started working with a public sector organisation who have 4 clustered sql instances that has 80% of it's db mirrored.
Looking at the transaction log - it seems that a transaction log backup is a good idea as the log is 4x larger than the data file.But I'm not allowed access to the physical server to check onto which drive I can create the trn. No RDP, no vmware - let's be honest I'm not even allowed to launch cmd line Also the Server Manager informs me "We will need to carefully look at database backups if you guys want to start doing these backups on box, as that will break our off box backup routine (it will screw the transaction chain)."
I don't understand how backing up the transaction log could break the "transaction chain"?
I want to set up a database role so that users can use sp_readerrorlog through SSMS. It does a check on membership in the securityadmin role.
I have tested it and can see you can grant execute on xp_readerrorlog but the SSMS GUI uses sp_readerrorlog.
I thought I could create a user/certificate and add the signature to sp_readerrorlog but it's not permitted (likely because it's not a normal database object).
So the other solution is to add the users to the securityadmin role but then explicitly deny alter any login (best done with a custom server role in 2012+ but otherwise just manually in 2008). I tested this out and it works, I'm not able to alter any logins or increase my own permissions, I also did a check of what's reported from fn_my_permissions(null, null) and it shows minimal permissions like I'd expect.
I am new to SQL Programming. I am learning the basics. I am trying to create a simple query like this -
SELECT Column_1, Column_2, Column_3, 10*Column_1 AS Column_4, 10*Column_2 AS Column_5,
-- I am not being able to understand how to do this particular step Column_1*Column_5 As Column_6
FROM Table_1 First 3 Columns are available within the Original Table_1 The Column_4 and Column_5 have been created by me, by doing some Calculations related to the original columns.
Now, when I try to do FURTHER CALCULATION on these newly created columns, then SQL Server does not allows that.
I was hoping that I will be able to use the Newly Created Columns 4 and 5 within this same query to do further more calculations, but that does not seems to be the case, or am I doing something wrong here ?
If I have to create a new column by the name of Column_6, which is actually a multiplication of Original Column_1 and Newly Created Column_5 "I tried this - Column_1*Column_5 As Column_6", then what is the possible solution for me ?
I have tried to present my problem in the simplest possible manner. The actual query has many original columns from Table_1 and many Calculated columns that are created by me. And now I have to do various calculations that involve making use of both these type of columns.
Here with i have attached the execution plan, In that i have tempdb spill over in sort operation. i have created index to sort even it needs temp db spill over. [URL]....
I've been trying to make the following query more performant by breaking it up into smaller pieces.
SELECT MT.A3+MT.A4 AS A34,MT.A3 -- ,M.* FROM Master_TAB M JOIN (SELECT M.A1,t3.A3,t3.A4,M.A6,M.A2,ROW_NUMBER() OVER (PARTITION BY A1,A6,A3,A4 ORDER BY A5 DESC) AS rownum
[Code] ....
I know that the Spill is caused by the Sort but I can't remove the sort (sort can't be done in front end). My master table had 1.7 million rows and almost 200 columns (bad design? I know but can't be changed as there's too much that would be affected) every row is little over 1KB
Here's my attempt...
-- MASTER_TAB has 1.7 million rows and 50 columns CREATE TABLE [dbo].[tmp_ABC]( [A1] [varchar](13) NOT NULL, [A2] [varchar](5) NOT NULL, [A3] [varchar](4) NOT NULL, [A4] [varchar](4) NOT NULL, [A5] [int] NULL ) ON [PRIMARY]
[Code] ...
This is the Query that is causing the Spill (in reality I'm supposed to bring back all 200 columns fro the master table but for debug purposes I limited the columns)
Select c.A3+c.A4 as A34, c.A3, c.A1 -- M.* from tmp_DEF c join MASTER_TAB M on M.A1 = c.A1 and M.A2 = c.A2 order by c.A3, C.A4
if I just run the following I get no spill:
Select c.A3+c.A4 as A34, c.A3, c.A1 from tmp_DEF c order by c.A3, C.A4
as soon as I add the Master table as a Join I get the Spill...
I read many articles, tried many suggested things (creating indexes... clustered, non-clustered) without success. Maybe I'm totally in Left Field and should enhance the performance going another route?
If I install an instance with Windows Only authentication, and then change it to Mixed Mode, if I enable the sa login, the password has already been set. What is the default? If it's generated, how secure is it? Is the password generated? What algorithm is used for that?
My sql databases in SQL Server 2014 has the status "suspend" as I saw in SQL Management Studio. I can't restore to serviceable condition sql databases through standard procedures. I need to restore .mdf file.
I am using a monitoring system where I can monitor a numeric SQL result assuming the result is one field and one row.I would like to do this to say monitor the free available space or percentage on say the Master database. DBCC SQLPERF gives me a few columns and results for all databases on the server.
In our environment applications are using a DNS name which points to the physical server ip address. Now we are planning to move to 2014. We are planning to have servers in different subnets so we will be having two ip adresses for listener. How we can point the DNS to the listener ips? If failover happens can the DNS point to the exact ip address of the listener where it's primary node?
"Process 0:0:0 (0x1e10) Worker 0x00000006B6D341A0 appears to be non-yielding on Scheduler 13. Thread creation time: 12906028806348. Approx Thread CPU Used: kernel 0 ms, user 0 ms. Process Utilization 13%. System Idle 84%. Interval: 70189 ms."
Is it better to run the profiler or performan counter?
What are the filters we have to select in the profiler to monitor the Sql server
I have a SQL server box running 2014 reporting services. I have another server running IIS v8.
I would like to be able to connect to the IIS site and be given the SSRS report browser.
So externally if I browse to [URL], I am presented with the report server interface, the same as if I browse to http://xxx.xxx.xxx.xxx/reports internally.
What is the best approach for a read only copy of a database that is ~ 1TB. The primary database is fed nightly with an ETL process. We are currently trying to duplicate the ETL to read only server but that process is not going well. So we are looking at other options to let SQL make the copy.
The primary database is on a Win12R2 with SQL 12 or 14, a 2 node A/P failover cluster.
The read only copy will be on a Win12R2 with SQL 12 or 14. It is not a requirement to fail over to the read only copy if the primary should go down.
What would best the approach to accomplish the end result?
I have 10 databases which are configured as principal in mirroring I need to failover all the databases as part of failover , instead of writing query each database as parner failover, is an script which will generate the databases as principal to failover ?
After installing SSMS on some computers - the only way we can get SSMS to run correctly is to run it as the administrator. Is there a way where you don't have to do that? These end users are logging as themselves and have accounts in SQL Server all set up - but SSMS will only launch for them if we right click and select "run as administrator".After doing some digging - it seems that this is a common problem out there.
