2
votes
1answer
32 views

What is the best storing device for DB transaction log?

I'm using MySQL with InnoDB storing engine. Transactional log is placed to dedicated HDD. Still as it is HDD atopsar shows big load (>50%) to this HDD because of big amount of small IOs (about 50 ...
0
votes
0answers
17 views

Joining 2 big tables turn into a server down problem

Recently I was using a database (MySQL with Workbench) in the company that I work for (I'm a business analyst, not a DBA), and wrongly I created a query joining 2 tables that basically are the same. ...
1
vote
2answers
219 views

Optimizing large MySQL SELECT WHERE IN clauses

How can the following SELECT WHERE IN case be optimized? I have a table with over 100 million rows with only 3 columns. The primary key (col1) is a 127 varchar. I am performing a SELECT col1 WHERE ...
1
vote
0answers
21 views

What is the best type of database for numerous multi-threaded access? [closed]

I am developing a simulation and have limited experience working with databases (very limited SQLite3 exposure). Here is my task: Server that stores a potentially large database (no size requirement ...
0
votes
0answers
36 views

Oracle 9i Low performance on Windows Server Enterprise 2003

I'm facing some problems with performance with my Oracle database running on a virtual machine with Microsoft Windows Server Enterprise 2003 with 8GB RAM. It works pretty well after the database is ...
2
votes
1answer
97 views

SQL Server - Data and Log Separation

We have a SQL Server 2008 R2 which has, among others, a 12K RPM HDD and a 7.2K RPM HDD. The original intention was to store the data files on the 12K drive and the log files on the 7.2K drive, as is ...
0
votes
1answer
159 views

How should I config the my.ini(or my.cnf) file for mysql?

Thanks for taking your time to look at my question, and I hope that you can help me with this. I have a Windows Server 2012 server, it has: Memory : 3840MB Ram Processor: Intel(R) Xeon(R) CPU ...
0
votes
4answers
100 views

T-SQL: Complete Database in one table

at a relational data model every logical relation is a single table with values and so on. I know someone who is this too much work and he wants to create only one table which contains all. This could ...
1
vote
5answers
410 views

How to determine why a MySQL server has become slow and requests sometimes time out?

I'm working on my first project that makes heavy use of a MySQL database and am struggling to understand performance issues I'm having. Most of the time, responses are returned quickly from the ...
2
votes
2answers
170 views

Autogrowth, shrink and database performance

I have already asked some questions about Autogrowth and shrink. But I have some doubts related to it. 1)I have a database which grows about 300 MB every month. So is it best to set Autogrowth of 300 ...
-1
votes
1answer
246 views

How can I detect which indexes are being rebuilt offline and how long?

The rebuild of indexes takes appr. the same 55 min. with both "Do not rebuild indexes and "Rebuild indexes offline" "For index types that do not support index rebuilds" with "Keep index online while ...
1
vote
2answers
55 views

What does enabling containment on server incur?

Having read in a book of Patrick LeBlank "Microsoft® SQL Server® 2012 Step by Step": "Benefits and limitations of contained databases As with most features, there are benefits and ...
5
votes
1answer
1k views

How to determine if there are [idle connections with] uncommitted transactions in PostgreSQL?

According to a comment on this question I asked about idle connections in PostgreSQL 9.2, some uncommitted transactions (possibly related to some of those idle connections) might cause some ...
5
votes
1answer
2k 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 ...
3
votes
1answer
63 views

Does avg_query for PgBouncer include update and inserts?

Trying to tune our application and would like to know if the stats data that pgBouncer shows as avg_query, according to the PgBouncer docs on usage: avg_query Average query duration in ...
6
votes
1answer
151 views

What is a good way to determine the performance I should expect from a PostgreSQL server?

Trying to figure out how I should expect my database to perform. Basically, I need to determine when the server I have set up is reaching its performance limits - which would help me plan server ...
4
votes
1answer
162 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 ...
3
votes
1answer
206 views

Load Testing Crash Course

Can someone point me at a good resource to get a crash course in load testing. I have a sql server machine that I need to load test but I havent been thruogh the process before. Also we do not have ...
3
votes
1answer
11k views

What queries is Oracle executing, how frequently, and time-taken?

I have a (Java) web-application, that of course executes many queries (selects, inserts, updates, deletes) to the Oracle Database. I want to find out the following for last 7 days: SQLQuery ...
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 ...
6
votes
1answer
3k views

Capabilities of InnoDB INSERT Performance

Hi I am running the most recent version of Percona Server. Server version: 5.5.24-55 Percona Server (GPL), Release 26.0 I have a 10 cpu box of these characteristics. processor : 0 vendor_id ...
3
votes
2answers
433 views

What exactly is “pinning” in relation to indexes?

When one talks about "pinning" in indexes, what exactly is this? Is there some other word/term I can search for, as google has not provided any solutions. It is part of a test question, where ...
8
votes
4answers
8k views

Why using innodb_file_per_table?

There are many articles exaggerating (IMHO of course) the need for innodb_file_per_table. I understand that with innodb_file_per_table, there should be a better control over the individual tables; ...
2
votes
2answers
624 views

How to compare performances of two databases

There are two database servers and I want to compare their performances. Both have Windows operating system and and Oracle (10.2.0.4 and 11.0.2) database. Both are OLAP databases with 15-20 users ...
3
votes
2answers
783 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 ...
3
votes
3answers
979 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
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 ...