The discipline of Operational and Architectural Management of Database Systems.

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2answers
3k 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 ...
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votes
3answers
7k 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 ...
4
votes
1answer
502 views

Sql Server - Running a Job on Multiple servers

I am using SqlServer 2008. I have a Sql Server Job that checks Disk Space and emails admins if the space is less than 15% Instead of adding that Job to all servers is it Possible to run the Job on ...
4
votes
3answers
4k 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
2answers
21k 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. ...
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3answers
25k 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
21k views

Script to see running jobs in SQL Server with Job Start Time

how to write script to see running jobs in SQL Server with Job Start Time? SELECT sj.name, sja.run_requested_date, CONVERT(VARCHAR(12), sja.stop_execution_date-sja.start_execution_date, 114) ...
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2answers
5k views

The best way to rename the tables after development completed

What is the easiest and most reliable approach to rename the database tables and columns in SQL Server 2008 r2? We have finished development and for some reasons, we are required to rename some ...
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2answers
2k views

How to remove identity specification for multiple tables

I am having total 109 table in Database and now i am migrating to Amazon server with identity insert and now i want to remove auto increment column specification for all tables. How set auto increment ...
4
votes
1answer
2k views

Confused about load balancing and horizontal scaling in postgresql [closed]

Please correct me if I am wrong but I guess handling more requests and load by adding more machines or balancing the load between multiple servers is horizontal scalling. So, if I add more servers, ...
4
votes
2answers
994 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.
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3answers
166 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.
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2answers
6k views

Generate sample data for an Oracle database [closed]

Good morning, What free [or trial] software can I use to generate sample data for an Oracle database? I've been trying with various tools, but none work. Thanks for all suggestions, Alec Taylor
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votes
1answer
231 views

Re-designing a Database cost and advice [closed]

The web application I am working with has a huge Database that is a real mess, no foreign keys, no constraints, no indexes, no optimization, no normalization, nothing. Until now, the logic has been: ...
4
votes
1answer
1k 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
1answer
644 views

SQL Server Restore from one database to another

One of our devs backed up a dev database, and then restored it in production. It's a new database for a new app that was deployed last night intentionally to prod. Now in the backupset table ...
4
votes
2answers
2k 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
493 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
794 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
813 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
3answers
1k views

Suggestion required for Large Database Optimization and performance

We are creating a large database with estimated growth rate 200 million+ records per annum. The database is use for analysis purpose and we will generate different tabular and graphical reports from ...
4
votes
1answer
193 views

Star join query optimization - Change partitioning, use columnstore?

I am trying to know the best possible way to improve performance of a query given to me by my client. It contains a few tables which are joined and one of table is called dwh.fac_sale_detail which ...
4
votes
1answer
545 views

Postgres pg_basebackup reports directory exists but is not empty

I have postgreSQL 9.4.1 installed on a Win 2012 Server. I am looking to setup replication between this and another server of the same spec. So I am following guidance on preparing the master ...
4
votes
3answers
190 views

What is a good guideline for sampling for statistics updates

Scope: A billion record table that is indexed in 10 ways. Rate of change per day is 1/2 a percent. Some of the indexes are monotonously increasing (datetime/timestamp), yet the common queries most ...
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 ...
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votes
2answers
1k views

Website is too slow when number of records increases?

I have developed a web application called Referral Program, It it developed by using PHP, MySQL. Users can joining the website and when they introduce new members, he/she gets a commission. The system ...
4
votes
1answer
35 views

SQL Server 2008 R2 services not coming online

I am working for a critical account and yesterday I got a weird issue after applying cumulative update package 14 on top of SQL Server 2008 R2 Standard edition. Before applying CU-14 package on the ...
4
votes
1answer
103 views

Getting a proxy account to backup to a share using Ola Hallengrens backup script

I have a SQL Server 2012 Standard install where the Engine and Agent are running under the default NT Service accounts Engine - NT Service\MSSQLSERVER Agent - NT Service\SQLSERVERAGENT I am trying ...
4
votes
1answer
924 views

How to drop all scheduler events in MySQL 5.6?

In MySQL 5.6 is there a way to drop all scheduler events with an administrative command or do I have to go through them one by one with DROP EVENT [IF EXISTS] event_name?
4
votes
1answer
352 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
201 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
67 views

SQL Server 2008 R2 : LDF file size not increasing

I am using SQL Server 2008 R2. I have a table statDB of 100 GB in primary filegroup. I have created a secondary filegroup in same database (Lab1) and created a table copyStatDB. Now I start copy ...
4
votes
1answer
428 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 ...
4
votes
1answer
24 views

Correcting French Characters in MySQL

I Have a huge MySQL table with a long list of charities. Some of the charities have French characters in them which appear incorrectly. For example I'm getting uppercase 'É' instead of 'é' in the ...
4
votes
1answer
50 views

Problem when add administrator for Analysis Server ( SQL Server 2008 R2 )

I'm trying to add a user as an administrator in Analysis Server, doing this: 1 - Connect - Analysis Server - Right click on the Instance - Properties - Security - ADD : This number was already ...
4
votes
1answer
2k views

Take individual MySQL database offline

MySQL does not have any SQL commands or internal mechanisms for making an individual database unavailable / offline moving an individual database Thtis being the case, how can you take an ...
3
votes
2answers
371 views

Getting all databases which a sql logon can connect

I need to know all databases in a SQL Server on which a user can connect. With sys.databases I get all databases and with sys.server_principals or sys.syslogins I get all server logons. But I can't ...
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votes
2answers
331 views

Database Schema for Blank Database is large. 20MB

Is it normal for blank databases with just schema to be large? Or is there a way that I can reduce the size of the initial database?
3
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5answers
10k views

Small sample database for practicing database administration?

I'm looking for a portable sample database that can be created from a script has a simple ER model has little data for database administration practicing purposes. I know that there is e.g. ...
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
2answers
2k views

Transferring Data from OLTP to OLAP databases

Systems that have both OLTP and OLAP databases periodically move data from the OLTP database to the OLAP database, so that reports can be generated based on the OLAP database. What's the official ...
3
votes
2answers
3k views

Database consistency checker in postgresql

Are there any DBCC(Database consistency checker) commands in PostgreSQL? I could find SQL server DBCC commands but not for Postgres? I read that postgresql has inbuilt functionality of perfomance ...
3
votes
2answers
587 views

How to identify unused databases on my sql server

I am looking for the best practices or analysis someone would have followed to identify the unused or inactive databases on my SQL Server. I went through many articles, which say possibly to go for ...
3
votes
3answers
448 views

Is this database fine for calculation?

I am doing an application called as Invoice Application.For that I have my database is like this. Now my problem comes when I am taking the tax part in my database.As I have made tax as an option ...
3
votes
4answers
6k views

What is the purpose of having a table NOT LOGGED INITIALLY

I came across this recently. When defining a table in DB2 LUW (at least 9.5 or higher), you can define it as NOT LOGGED INITIALLY. Example from the book I read: CREATE TABLE products ( productID ...
3
votes
1answer
19k views

How do I open a MySQL Database Dump?

I work for a doctor's office, and we are in the process of switching EMR systems. The previous system has provided a physical 'dump' of the database. I however, don't know how to open this database ...
3
votes
1answer
165 views

PostgreSQL doesn't use all the RAM it could

I'm having performance issues with my PostgreSQL 9.4.1 server. I have tuned the server using the usual best practices (pgtune + google). Here's the relevant config: # <snip> the default config ...
3
votes
2answers
181 views

Historical dbcc checkdb results

Is there a better way of accessing historical dbcc checkdb result history (if output logging was not used at runtime) than xp_readErrorLog? EXEC xp_readErrorLog {0-20}, 1, N'CHECKDB'; SQL Server ...
3
votes
1answer
186 views

Unable to start SQL Server Browser service in Sql server 2005 [closed]

we are unable to start the SQL browser service on one of our machine with below error: I believe this to be the reason, why we could not connect to the instance with below error: I tried ...
3
votes
3answers
7k views

What are the risks of copying MDF/LDF files without detaching the DB first?

Where DB backups are not available, our support team has been trained to restore using the following steps: Get a copy of the MDF/LDF from a file system backup. Stop the instance. Overwrite the ...