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6
votes
2answers
3k views

Oracle clean up

I have an Oracle database on a VMWare image that seems to be slowly eating all my available disk space. I would like to know if there is a command or script that would perform some kind of clean up of ...
16
votes
7answers
497 views

Which of these table designs is better for performance?

I have been asked to create something which tracks the daily cost to collect on accounts, and I am trying to figure out a database table schema that would support this. Here's what I know Company ...
8
votes
2answers
9k views

PostgreSQL: Using schema and table names from other tables?

Consider the situation where I have all my schema names in one table and all my table names in another table. Is it possible to do something like in the following (pseudo-code)? SELECT value FROM (...
4
votes
2answers
221 views

Performance of SQL Server indexing

I want to see the performance differences between an indexed vs non-indexed column when running the same query. The table I've created (FileCollection) is very simple and has the following 3 columns ...
11
votes
7answers
222k views

How check that the Oracle Database is up?

For our application we have a configuration file for connecting to the Oracle database (URL, username, password). The application takes 2-5 minutes to start. If there is something wrong with ...
6
votes
3answers
6k views

Too Many Connections

I'm using MATLAB to feed the database but after a time I'm getting a too many connections error. I always using opendb and closedb in pair. Is it to fast the feeding? Do I have to wait after I ...
3
votes
1answer
857 views

SQL Server Embedded Edition vs SQLite

Can anybody shed some light on how these SQL products compare? No need for essays, only highlights such as "X supports this, while Y doesn't". How is efficiency affected as the database grows larger ...
3
votes
1answer
2k views

Getting error on SQL Server

I am getting these error messages one after the other every week on Win 2008 and SQL 2008 R2. MAX DOP is set at 1. Any idea how I can solve this? Thanks. DESCRIPTION: A fatal error occurred ...
3
votes
1answer
914 views

sysarticles system view - what does a status of 57 mean?

I'm trying to work out why one article within a publication isn't replicating. I've scripted it out and confirmed the replication procs it's supposed to call are the correct ones, and have run a trace ...
22
votes
3answers
6k views

Efficency of stored procedures vs raw queries

I have read much on both sides of this debate: is there a signficant performance gain to be had by using only stored procedures over raw queries? I am specifically interested in SQL Server but would ...
6
votes
2answers
314 views

How can I secure my database code?

We have a lot of proprietary database code that is simply encrypted using the "WITH ENCRYPTION" option. Unfortunately, this is a very weak method of securing database code. Is there any better way ...
24
votes
3answers
11k views

Why is `SELECT @@IDENTITY` returning a decimal?

I'm using Dapper to execute the following query against a SQL Server 2008 R2 Express instance from a ASP.NET MVC 3 (.NET 4.0) application. INSERT INTO Customers ( Type, Name, Address, ...
11
votes
2answers
167 views

A question on SARGability

I just need to confirm that I understand something correctly: I recently viewed an SO question in which a user posted an answer in Linq like: from p in db.table where p.column.AddMinutes(1) > ...
5
votes
1answer
189 views

How big of an impact does NUMA really have?

I was reading up on Non-Uniform Memory Access (NUMA) and I was wondering how much of a difference it can really make? Another way to word that, what level of throughput is required before this ...
20
votes
5answers
13k views

Do empty columns take up space in a table?

I have table that holds from very basic info. Just a title and a few date fields. There's one field called comments which is varchar(4000) Most of the time we leave it blank, but some times will enter ...
3
votes
3answers
2k views

Instant File Initialization | Lock Pages in Memory Issues

I have a server that I'm coming onto performance tune and for the life of me I can'g get these rights enabled. So I ran PS SQLSERVER:\SQL\NOFAULT2010\DEFAULT+sa\> whoami nofault\administrator ...
22
votes
2answers
16k views

How do you reset the sa password?

I lost the sa password on a machine, and when I log in to the machine directly using an account in the admin group, SQL Server Management Studio will not allow me to log in using Windows ...
2
votes
1answer
2k views

Moving Tables Indexes to Separate file / file-groups, What Happens?

I'm trying to get a grasp on whats going on when you move objects to a separate filegroup / .ndf file. *This is for a 3rd party app that sucks that I have no access to source, and is entirely Ad-...
8
votes
1answer
9k views

Database Users and Server Logins and the Mapping between them

I have an instance of SQL Server 2008 R2 Express Edition at home and another on a server at a clients premises which I am using to develop an application using Access as the front end. This ...
3
votes
1answer
887 views

Database Design: Storing Map Locations

When working on a game, I developed a database that used X/Y coordinates, roughly as: CREATE TABLE Map ( MapId INT IDENTITY PRIMARY KEY, X INT NOT NULL, Y INT NOT NULL, North INT ...
25
votes
1answer
704 views

Reporting Service and Application Role

First poster, long time lurker here. What is the best way to activate application role in a report ? I've tried different things and so far the only method that works is to embed the call to the ...
10
votes
2answers
3k views

DTA Recommends to CREATE STATISTICS

I just ran a T-SQL query through DTA and one of the recommendations is to CREATE STATISTICS on one of the columns that is part of many of the queries in the SQL code file. My question is, how exactly ...
2
votes
2answers
5k views

Storing images in MySQL db — type? [duplicate]

Possible Duplicate: Is it better to store images in a blob or just the url? I need to recover images from an XML file stored on a remote server and save it to my database. Not sure how I should ...
6
votes
2answers
146 views

In SQL Server 2005 how would I determine the minimal permissions a user requires?

I'm the accidental DBA of my group and I've inherited a database that follows a number of bad practices. Currently every login is a member of the sysadmin group. What is the easiest way to determine ...
36
votes
7answers
65k views

Is it possible to mysqldump a subset of a database required to reproduce a query?

Background I would like to provide the subset of my database required to reproduce a select query. My goal is to make my computational workflow reproducible (as in reproducible research). Question ...
-2
votes
0answers
181 views

how to retrieve data from a table using Foreign Key [duplicate]

Possible Duplicate: Get a record of one fields and also of the Foriegn Key I have 2 tables CountryMaster(CountryID,CountryName) StateMaster(StateId,StateName,CountryId) I want such a query that ...
4
votes
1answer
777 views

Does T-SQL MOVE actually move the database, or just copy?

I'm a bit confused over the T-SQL command MOVE. I have a statement saying: MOVE N'Prod_Database_Data' TO N'C:\Program Files\Microsoft SQL Server\MSSQL10.MSSQLSERVER\MSSQL\DATA\Test_Database.mdf' ...
7
votes
1answer
13k views

How do you increase MySQL performance using current server resources?

I have a MySQL database and some of my queries became slow. Query time is not stable. Most of the queries are fast, but some of them (may be that reads and returns less data) take long time. I know ...
15
votes
3answers
881 views

Are heaps considered an index structure or are they strictly a table structure without index?

Inspired by this post: https://twitter.com/#!/SQLChicken/status/102930436795285505 Heaps: Are they considered an index structure or are they strictly a table structure without index?
9
votes
3answers
5k views

Users complain that system runs slow when mysqldump is in progress

The MYSQL database (ibdata1) is of size 73 GB and is configured to run as a dedicated database server on Windows 2008 O/S for INNODB tables. We are running the backup using mysqldump mysqldump --...
45
votes
5answers
46k views

When should you denormalize?

I think we are all familiar with database normalization. My question is: What are some guidelines that you use when you want to denormalize the tables?
8
votes
1answer
2k views

Understanding SQL Server permissions

I am rooting around in SQL Server Management Studio against my instance of SQL Server 2008 R2 Express Edition. I am trying to understand how the permissions work. What I can see is (via the ...
8
votes
3answers
593 views

When are procedural queries absolutely necessary?

I know that we tend to avoid cursors and loops within SQL Server at every cost, but what are some of the situations where you absolutely need procedural queries, and set-based queries just will not ...
15
votes
1answer
13k views

Cannot drop anonymous user from mysql.user

I am trying to DROP the anonymous users from my mysql.users database. However, I have been getting odd behavior. When I enter the command: DROP User ''@'WOPR'; I was getting a generic error message. ...
12
votes
2answers
10k views

What exactly is a database engine?

I have gone through the definition on http://en.wikipedia.org/wiki/Database_engine several times: A database engine (or "storage engine") is the underlying software component that a database ...
10
votes
1answer
2k views

Why can't we perform joins in a distributed database like Bigtable?

From this answer to "What database does Google use?": Bigtable is not a relational database. It does not support joins nor does it support rich SQL-like queries. Is this obvious? I do not ...
6
votes
2answers
1k views

Table contains multiple names for same company

I have a table of monetary transactions that has a field for who the money was paid to or received from. Transactions are recorded using info from paper invoices, paper reciepts, internet reciepts, ...
3
votes
2answers
145 views

Get a count of shippable orders

I have two tables: orders and order_lines. I need a fast, inexpensive way to display a count for orders that are going to be shipping today. The order_lines table is associated with the orders table ...
2
votes
2answers
5k views

Getting current date as part of an Stored Procedure

I have the following SP: SELECT moncallAdd.FirstListing, DATEADD(MINUTE, mOnCallAdd.StartOnCallTime, DATEADD(DAY, mOnCallAdd.StartOnCallDate, '12/31/1899')) AS OnCallStart, DATEADD(...
10
votes
2answers
11k views

Performance of a Trigger vs Stored Procedure in MySQL

A post here on DBA.StackExchange (What are the best practices for triggers to maintain a revision number on records?) has spawned an interesting question (at least, interesting to me) regarding ...
5
votes
2answers
6k views

Why is mysqldump file so large?

We have a 2GB MySQL DB. We started a mysql dump of this DB this morning and the resulting dump file is 27GB! Can anyone shed some light on what's going on here? Questions Why is this file so large? ...
3
votes
4answers
223 views

how to interpret log files with high transactions

I'm having this issues with too many logs files being generated. Over 60gb in the last 24 hours. It's not a massively high transactional website. What is the best way to read the log files and work ...
16
votes
3answers
18k views

Which DBMS is good for super-fast reads and a simple data structure?

I am developing a product that, as a part of it's operation, must track a large number of files/directories. The idea is to store stat information in a database then, on boot, create watches for each ...
7
votes
1answer
3k views

Transaction and data consistency during a failure

When a database begins a transaction, all statements executed in that transaction are isolated and atomic (and consistent and durable). These are pretty much the definition of a transaction. ...
4
votes
3answers
1k views

What are the 'free to use' workload generators available for Oracle? [closed]

A couple that I know about are http://www.dominicgiles.com/swingbench.html and http://hammerora.sourceforge.net/ Are there any others? I am looking for tools what can generate random workload (based ...
2
votes
3answers
4k views

What are the best practices for triggers to maintain a revision number on records?

I have an audit trail implemented on an application database that captures old value, new value, modification time, and user inserting it into another table. I'm now wanting to add a revision number ...
8
votes
2answers
9k views

Difference between EXEC() and sp_executesql with no parameters?

I just learned about the new sp_executesql stored procedure. I like the fact that there's a way to execute parameterized code from within SQL Server. But, I'm wondering what the difference is ...
5
votes
7answers
593 views

Policies RE database triggers in well-designed applications?

I've heard all kinds of horror stories around gremlins living in database triggers, and--worse--systems being brought down by the addition of a trigger that caused a chain of cascading ones. I'm ...
11
votes
4answers
4k views

overstating field size in database design

I have some fields for my tables that are strings and at the moment, most of the field size have pretty high character limits. For instance, 100 char for the street name. Is there a penalty for using ...
3
votes
1answer
222 views

Minimum rowcount for filtered index?

Creating an index always has trade-offs. Whenever you insert, update or delete, it has to perform those operations on the index as well. This is all pretty commonly known. But with the advent of ...

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