The discipline of Operational and Architectural Management of Database Systems.

learn more… | top users | synonyms

5
votes
1answer
812 views

Does dropping a Primary Key constraint from a Partitioned Table break the partition?

We have a table partitioned on a date column. The Primary Key for the table is a composite key of this date column and 4 other columns. We are thinking about dropping the Primary Key constraint from ...
5
votes
2answers
2k views

Rebuilding index has impact on mdf/ldf files SQL Server 2008

While rebuilding index have used option 'SORT_IN_TEMPDB = ON' in order to avoid unnecessary growing your user database files. What does it exactly means? Is complete process done on TempDB and does ...
5
votes
2answers
22k views

How to create Sql Server login for a domain account?

All, I have Sql Server 2008 installed on a server (let's say Server1) in a Domain (let's say AD). I also have a domain account called AD\Sql1. This is not an Admin account on the Domain (AD), but I ...
5
votes
1answer
187 views

How do I track logins, connections, user accounts, queries, …?

I am a BI person who has been asked to step in and pretend I am a DBA. I am not a novice with databases but AM a novice at the admin type stuff. We have a SQL Server database that is going to be ...
5
votes
1answer
472 views

Expanding a partitioned table

I have a table that holds four years of data, where for each month I have a partition that is based on a filegroup with two files. Unexpectedly, I received eight more years of data and prepared the ...
5
votes
3answers
279 views

Bad use of Oracle Tablespaces

I have a doubt about the use of oracle tablespaces. I've decided to define for each schema of the datababase two different tablespaces (one for data, and another one for indexes). The problem is that ...
5
votes
1answer
3k views

Appending backups while overwriting expired sets

I've been reading up on this, but the online documentation is a bit difficult to understand and seems awkwardly written. For example the INIT, NOINIT. One says it will try to overwrite everything. ...
5
votes
2answers
2k views

What is the point of the TABLE_CATALOG column in INFORMATION_SCHEMA.TABLES?

In MySQL's table INFORMATION_SCHEMA.TABLES, there's a column named 'TABLE_CATALOG'. The documentation is sparse on this column and I'm wondering what the heck is the purpose of this? Any killer-app ...
5
votes
2answers
128 views

Is it somehow possible to predict / foresee when SQL Server will trigger auto-growth?

I found numerous questions / answers about SQL-Server auto-growth - almost all indicating that one should try to avoid auto-growth if possible. However auto-growth is available with MS SQL Server and ...
5
votes
1answer
1k views

Mongo Collection `Size` is *larger* than `storageSize`?

I recently compacted my collection using the command: db.<collectionName>.runCommand( "compact" ) And now my collection size seems to be bigger than size on disk! SECONDARY> ...
5
votes
1answer
273 views

Is there a standard approach to rolling out database schema changes?

A developer said I should simply wrap all my database upgrade scripts in a transaction. If it fails, just roll back all changes. All my instincts tell me this is wrong, especially when it comes to ...
5
votes
2answers
504 views

How to properly configure PostgreSQL RAM usage?

Using PostgreSQL, we have several hundred concurrent processes doing regular database access. We have our data spread out through several database servers, each of which houses a connection pool with ...
5
votes
2answers
421 views

SQL Server - DBO without Backup

Similar to my previous Question : Prevent Non Copy Only Backups, how do I create a user that can do everything to my database take backups at all. I've granted them every role except ...
5
votes
1answer
97 views

SQL Server 2012 Unable to Utilize Defined Amount of Locks

So I've been beating my head against the wall for two days about this and I can't find a solution. I'm running a script to stage a large amount of data. This script requires roughly 35 million locks ...
5
votes
1answer
3k views

Could too many idle connections affect PostgreSQL 9.2 performance?

Some queries on my database server seem to take a long time to respond, and I believe the CPU usage is high. When running ps aux, I see ~250 "idle" connections (which I believe to be too many). I ...
5
votes
1answer
656 views

Does PgBouncer create a separate pool for every database config entry?

If I set up a pgbouncer.ini config file with several database entries, does pgBouncer create a separate pool for each one? I would think so, but have not been able to confirm this. For example, ...
4
votes
3answers
4k views

How to reduce the log file size without shrinking it in SQL server

In SQL server, how do you reduce the log files size without (DBCC) shrinking it. I know shrinking the log file will free up some space, but will also cause fragmentation. Doing a checkpoint in simple ...
4
votes
4answers
411 views

Recommendation for free event monitoring software

I'm seeking recommendations for free / open event monitoring tools. HPOV costs continue to multiply like so many wet gremlins, and we've had enough. There are some interesting suggestions in this ...
4
votes
1answer
3k views

ERROR: database “dbname” does not exist

According to the documentation, so long as I'm not connected to a database, I can either delete a database in the console using: DROP DATABASE dbname; Or I can drop it using the wrapper tool ...
4
votes
2answers
2k views

One filegroup, multiple datafiles, how to get list of tables in each file

In one of my production databases, I have a filegroup with 3 data files sitting on 3 different disks. There are over 50 tables on this filegroup. How do I identify the location of each of the 50 ...
4
votes
2answers
12k views

How to backup IBM DB2 Database online?

I tried to backup the IBM DB2 (LUW) Database using this command: ./db2 backup database DBEMP to /home/user1/db2bkup But I got this message: SQL1035N The database is currently in use. ...
4
votes
2answers
573 views

Update Statement takes forever to complete [closed]

I have table around 1250000 records, and 80 columns Table Structure CREATE TABLE [dbo].[Table] ( [Column1] [int] IDENTITY(1, 1) NOT FOR REPLICATION NOT NULL, [Column2] [int] NULL, [Column3] [int] ...
4
votes
3answers
2k views

How can I dynamically back up all SSAS databases on a given instance?

I want to dynamically back up all the databases on a given SSAS instance using a SQL Agent job (which would most likely involve executing an SSIS package). It is imperative that this is a dynamic ...
4
votes
3answers
18k views

Oracle 11g - Create Database fails?

I've just installed Oracle 11g and linked it to SQL Developer. I want to create a database for my django install. CREATE database 'django'; Error starting at line 1 in command: create database ...
4
votes
2answers
1k views

Creating partitions on a production database

I have a production MySQL 5.1 database that is running well but I want to improve query performances. I have never used Partitions and just going through the manuals. I have two tables that involve a ...
4
votes
2answers
476 views

Why monitor bytes sent and received on mysql

I want to know why we should monitor bytes sent and received on mysql ? I hope I have not asked a vague question. Thanks.
4
votes
3answers
150 views

Can anyone describe the step by step process of recovery , backup and restore in sql server

Can anyone describe the step by step process of recovery via backup and restore in SQL Server 2008. If possible please include some examples.
4
votes
2answers
1k views

How to Correctly Estimate the Average Number of I/O Operations my RAID 10 disk can offer?

The average Input/Output Operations per Second a disk can sustain is a very important factor in the tuning of MySQL / InnoDB databases, as it drives the speed with which Dirty InnoDB Buffer Pool pages ...
4
votes
1answer
370 views

Can I check what the allocation unit size is on my drives via a query?

Assuming that I do not have access to windows server, can I run a script from SSMS that would allow me to check whether allocation unit size is formatted with 64K?
4
votes
1answer
615 views

What are the concepts that need to be gone through for MySQL DBA?

I am a MySQL Developer, besides I am handling some DBA activities like backup, restore, mysql installation, etc at a top level. Now I wanted to shift to DBA, So I wanted to know in depth, like which ...
4
votes
2answers
3k views

mysql multi threading for a single query

I have big db of size 8GB and having 9 million contacts in this db. When we try to retrieve all contacts, it takes nearly 1 or 2 hour (in some cases result in timeout) to retreive all contacts for the ...
4
votes
1answer
601 views

Any way to send notifications to different Emails on success/failure of SqlServerAgent job?

SQL Server 2012 R2 on Windows Server 2008R2 Is there any way to send notifications to different Emails: on success of an Sql Server Agent job to one Email address and on failure - to another ? ...
4
votes
2answers
221 views

What are sensible/rational character limits in a database e.g. for a persons name

This is a general question about database admin. Is there some kind of standardization for character limits on fields in a DB? It makes sense to specify character limits on the database end for ...
4
votes
2answers
559 views

Isolation Level for a Data Warehouse

We are building out a data warehouse (and also some data marts as well) in our organization. My DBA skills have mostly been on OLTP type applications, but I am moving into supporting OLAP for our ...
4
votes
1answer
2k views

823 errors on tempdb

Have a couple Fiber channel SAN-attached cluster servers which have been intermittently reporting errors like: 2012-05-09 16:31:54.13 spid74 Error: 823, Severity: 24, State: 2. 2012-05-09 ...
4
votes
1answer
206 views

High amount of Read Misses and Pages To Be Flushed

I am running a mysql database backend for a Moodle installation, and after a few months performance really starts to suffer (Up to 30 seconds for some pages to load). Under investigation in the InnoDB ...
4
votes
1answer
171 views

After Rackspace server creation, PostgreSQL query planner doesn't work as expected

We created an image of one of our database servers in Rackspace. Then, we created a new server using that image, expecting things to work. However, the index performance we have seen seems to be ...
4
votes
1answer
103 views

How can I copy specific tables into one SQL Server Table into a separate table automatically?

I'm not sure if this is possible. Looking for some help with a specific issue. I am building an iPhone application with a data layer written in Ruby that will connect to SQL Server 2008. For various ...
4
votes
2answers
2k views

efficient way to poll database?

I have a Linux CentOS server hosting an Oracle 11.2 database, which communicates with an application server, which communicates with a client (a Flex application). I'll try to describe the pseudo-code ...
4
votes
2answers
2k views

How do you find home information for Oracle RAC on Unix?

Need help finding Oracle home path corresponding to a database instance in RAC environment. I am aware of few of the ways to achieve the same. Listing them below to avoid the same answers. ...
4
votes
1answer
2k views

When dedicated server process model should be used instead of shared process model?

It looks like Oracle shared server process model is better than dedicated server process model. In a shared server configuration, client user processes connect to a dispatcher and it can support ...
4
votes
1answer
290 views

Speed inserts in database with a table with +47 million data per each year, containing more than 10 years?

I'm moving my database to mysql but there is one table that is pretty big (more than 47 million rows for each year) and it takes years to insert all the data. I already tried everything I found in ...
4
votes
1answer
383 views

Oracle AWR shows missing stats for SQL ID as top elapsed statement

Why SQL ID has null number of executions and elapsed time / execution in AWR report. SQL ID is among top elapsed command on AWR but no details stats whoing time / execution. Would it be because shared ...
3
votes
3answers
2k views

How do I monitor bandwidth used by SQL Server on port 1433?

I have a single server running a .NET web application and a SQL Server database (2008 Standard). I'm planning to move the database onto a separate server but in order to provision the network hardware ...
3
votes
2answers
6k views

Reset IDENTITY value

I have a table with an IDENTITY column. While developing I delete the rows from time to time and add them again. But the IDENTITY values always kept increasing and didn't start from 1 when I added ...
3
votes
5answers
195 views

Does DBA need (a read) access to virtualization infrastructure? And why?

I am in charge of monitoring, troubleshooting, tuning and optimizing a few dozens production SQL Servers 2008 R2/2012 in my company that are being run inside VMWare virtual machines. I've requested ...
3
votes
2answers
1k views

VACUUM and VACUUM FULL do not return space to OS

I'm running Postgres 8.3.3. I have a postgres database on a Linux filesystem that is quite full. I've run VACUUM and VACUUM FULL, yet none of the space has been returned to the OS. When I observe ...
3
votes
3answers
3k views

Issue after moving the ib_logfile1 and ib_logfile0 files

I wanted to increase the innodb_log_file_size for better performance. And I increased it from the default value to 256 MB. As usual I got the error saying InnoDB: Error: log file ./ib_logfile0 is of ...
3
votes
2answers
589 views

Perl vs Ksh for Unix Database Administration

I realize this is a somewhat more subjective question, but I am looking to the community for guidance. Our company is fairly new to having DBAs. We used to use DB2 for i on the IBM's iSeries servers, ...
3
votes
2answers
4k views

SQL Server Connectivity Issues

I am getting the below error on occasion. Maybe every 30mins or so. I am not sure how to track what is causing the issue. I think it could be a Network problem as there are disk backups running as ...