Microsoft's SQL Server is a relational database management system (RDBMS) that runs as a server providing multi-user access to a number of databases. It originated from the Sybase SQL Server codebase, which is why both products use the extension of SQL called Transact-SQL (T-SQL).

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Recommendations for MS SQL Server monitoring software or service? [closed]

I have a client with MS SQL Server instances (2000, 2005) scattered across 20-30 servers. I've been engaged to get things organized and will be periodically reviewing the state of the database ...
5
votes
2answers
6k views

Splitting TempDB into multiples files equal to number of CPUs

The article SQL Server tempdb Best Practices Increase Performance suggests that I should split tempdb into a number of files equal to the number of cores. So for 4 cores you get 4 files. By ...
18
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2answers
4k views

Why does SQL Server require the datatype length to be the same when using UNPIVOT?

When applying the UNPIVOT function to data that is not normalized, SQL Server requires that the datatype and length be the same. I understand why the datatype must be the same but why does UNPIVOT ...
16
votes
2answers
3k views

Why do wildcards in GROUP BY statements not work?

I am trying to make the following SQL statement work, but I get a syntax error: SELECT A.*, COUNT(B.foo) FROM TABLE1 A LEFT JOIN TABLE2 B ON A.PKey = B.FKey GROUP BY A.* Here, A is a wide table ...
12
votes
4answers
12k views

Can I add a unique constraint that ignores existing violations?

I have a table which currently has duplicate values in a column. I cannot remove these erroneous duplicates but I would like to prevent additional non-unique values from being added. Can I create a ...
12
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3answers
3k views

Is there a reason to update statistics manually?

In SQL Server, statistics are updated automatically when Auto Update Statistics in True (which is the default). Is there a reason to update statistics manually and in what circumstances?
8
votes
3answers
856 views

sql server database sharding - what to do with common data / non sharded data

We have a very large scale enterprise level database. As part of our business model all web users hit our web servers at the same time each month which in turn hammer our sql box. The traffic is very ...
6
votes
1answer
20k views

Finding last time table was updated?

The query: SELECT name AS TableName, create_date AS CreatedDate, modify_date as ModifyDate FROM sys.tables order by ModifyDate will tell me the last time a table was created and modified (from a ...
5
votes
1answer
2k views

Allow non-sysadmin, non-owner of a SQL Server Agent job to execute it

I have a job that runs an SSIS package. Currently the owner is a proxy account. I can run the job manually from a sys-admin account. Our web service logs in using a limited account. It needs to ...
3
votes
2answers
134 views

SQL server tools to identify query optimisations and missing indexes [closed]

I have a broad question regarding SQL Server that was given to me on a quiz and I am not sure what the answer is as I do not have access to SQL Server at home. My question is how can I utilise SQL ...
3
votes
1answer
1k views

In MS SQL how do I find out what tables have not been queried or updated in a long time?

I'm maintaining a database that is being shared by a few systems. Over the years a few of those systems have been deprecated and lots of the tables are actually orphaned. Is there a query I can run to ...
18
votes
4answers
2k views

What are the consequences of setting varchar(8000)?

Since varchar takes disk space proportional to the size of the field, is there any reason why we shouldn't always define varchar as the maximum, e.g. varchar(8000) on SQL Server? On create table, if ...
14
votes
3answers
11k views

How does shrinking a SQL Server log file affect performance?

I have a SQL Server 2008 database that has a data file of some 2GB in size, but the log file is over 8GB. With pre-2008 databases I could use the 'Backup log' and the TRUNCATE_ONLY option but this is ...
13
votes
2answers
16k views

How To Profile Stored Procedures

I am using SQL Server 2012 and was wondering how to profile stored procedures For instance can profiler capture each individual SQL statement in a stored procedure, what it is, and how long it takes ...
12
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4answers
4k views

Is it possible to increase query performance on a narrow table with millions of rows?

I have a query that is currently taking an average of 2500ms to complete. My table is very narrow, but there are 44 million rows. What options do I have to improve performance, or is this as good as ...
11
votes
1answer
813 views

Behavior of data in indexes based on fill factor

Let's say you have a database where the default fill factor is 20. Whenever data is inserted, does it only create pages filled up to 20%? From my understanding, when the data is inserted there ...
10
votes
6answers
6k views

Suddenly Slow Execution Plan for Stored Proc

I'm trying to understand an issue we're having with SQL Server 2000. We are a moderately transactional website and we have a stored proc called sp_GetCurrentTransactions which accepts a customerID, ...
8
votes
4answers
673 views

Is a join optimized to a where clause at runtime?

When I write a query like this... select * from table1 t1 join table2 t2 on t1.id = t2.id Does the SQL optimizer, not sure if that is the correct term, translate that to... select * from table1 ...
8
votes
1answer
11k views

Why do we need to rebuild and reorganize Indexes in SQL Server

After searching the internet i couldn't find the reason for Why do we need to rebuild and reorganize indexes in SQL Server ? what does internally happens when we rebuild and reorganize ? An ...
8
votes
3answers
252 views

Nonclustered Index Insert

Say I have a table like this: create table SomeTable ( id int identity(1, 1) not null primary key clustered, SomeString1 varchar(50) not null, SomeString2 varchar(50) not null ) go ...
8
votes
5answers
9k views

Pros/Cons Using multiple databases vs using single database

Working on a new project which has the requirement to use 7 databases. Arguing performance, stability, optimization is easier implemented. While I don't agree I'm having trouble collecting good ...
8
votes
2answers
10k views

Difference Between Row Level and Page Level Locking and Consequences

When attempting to run my Maintenance Plan, I receive the following error: Executing the query "" failed with the following error: "The index "" (partition 1) on table "" cannot be reorganized ...
7
votes
2answers
26k views

What is the easiest way to move data from Oracle to SQL Server?

One of our products supports both Oracle and SQL Server as database backend. We have a customer who wishes to switch from an Oracle backend to Microsoft SQL Server, which isn't a typical transition ...
7
votes
2answers
4k views

What are the differences between SQL I/O Sim and SQL IO tools?

I want to test my different SQL Server alternatives with a benchmark tool. I found two tools by Microsoft: SQLIO Disk Subsystem Benchmark Tool SQL IO Sim What are the differences between them? is ...
7
votes
1answer
4k views

SQL Server Deadlock Graph - Table, Page or Row Lock?

Is there any way to decipher if a lock in a deadlock graph is Table, Page or Row level? I have all the information I need from the graph, including the Isolation Level, (2) but I really want to know ...
6
votes
3answers
204 views

Check server activity with code

I would like to see the activity on of the SQL server. So I can run a query when the server load is low. I know there is an activity monitor in SQL server but my company doesn't want me to give the ...
6
votes
4answers
23k views

SQL performance issues with remote query across linked server

This sproc create proc dbo.Get_Accounts as begin declare @current_date datetime set @current_date = dbo.fn_currdate() select [fields] into dbo.current_accounts from ...
6
votes
1answer
4k views

Whats the difference between Transaction logs and Binary logs?

Coming from a SQL Server shop, I now work with MySQL and I was curious. What are the differences between MySQL's binary log and MSSQL's transaction log? By the outlook thus far, it seems that there ...
5
votes
2answers
3k views

SQL Server - Tempdb data/log file placement

Currently we got TEMPDB Data (number of data files:2) and LOG file on same drive. On monitoring we have found I/O issues on TempDB. We got an extra drive available - should we move the TempDB Log ...
4
votes
1answer
4k views

What does role db_owner allow

I have been trying to troubleshoot a login that is not able to view certain tables in a SQL Server 2012 database. In doing so I find I don't quite understand what membership in the db_owner role ...
4
votes
3answers
661 views

Why does my procedure run slowly until I update statistics?

I am using a SQL 2008 database (not R2 sadly but have also tested this on an R2 database server) and have an ELT process running. Data is extracted from source and loaded to staging tables in the ...
4
votes
2answers
4k views

Why is SQL Server memory showing in task manager

I have worked with SQL Server for a while now, and I understand that SQL memory is inaccurately reported by the task manager. However I have recently been doing some testing on SQL Server that ...
4
votes
2answers
4k views

SQL Server replication subscriptions marked as inactive

Is there any way to force SQL Server NOT to mark subscriptions as inactive, ever? It happens sporadically when there are connection issues and I don't want to have to reinitialize the subscription ...
4
votes
2answers
4k views

Problem Reaching VM SQL Server Instance

Here's what I'm working with right now. I have a host OS which includes a SQL Server 2008 Enterprise instance. I have a virtual machine running on this host which has a SQL Server 2008 R2 Express ...
2
votes
1answer
655 views

How to schedule jobs in Sql server 2008 for less than 10 sec?

I want to run a job every 3 seconds, however in SQL Server 2008 we cannot define an interval of less than 10 seconds. The job is used to insert/update visitor information, and segmentation ...
0
votes
2answers
209 views

Determine whether there is any blocking while deleting large number of records [closed]

I would like to know whether there is any way to determine why it is taking too much time say 3 minutes for deleting 50K records from a database hosted in Sql Azure. I have clustered index on primary ...
0
votes
2answers
2k views

help in multi-language medical database?

My project is to design a medical database for many countries. This database contains many parts: medicines, medical centers, patients, etc. for every country with its own language. I started my ...
14
votes
5answers
8k views

Why does a UNIQUE constraint allow only one NULL?

Technically, NULL = NULL is False, by that logic no NULL is equal to any NULL and all NULLs are distinct. Shouldnt this imply that all NULLs are unique and a unique index should allow any number of ...
14
votes
2answers
8k views

Difference between SQL batch, statement and RPC?

What is the difference between SQL batch, T-SQL statement and Remote Procedure Call? How can I tell if part of the T-SQL code is a batch or statement?
12
votes
4answers
4k views

When was Torn Page Detection and Checksum introduced to SQL Server and what are the upgrade behaviors?

There are two different options in modern SQL Server for page verify; being Torn Page Detection and Checksum. None is also of course an option. I believe Checksum was introduced in SQL Server 2005 ...
11
votes
2answers
3k views

SQL Server VARCHAR Column Width

Searching around the web, I have found conflicting advice on whether there is a performance impact when specifying overly-wide VARCHAR columns, e.g. VARCHAR(255) when VARCHAR(30) will probably do. I ...
10
votes
3answers
795 views

Optimizing a CTE hierarchy

Update below I have a table of accounts with a typical acct/parent account architecture to represent a hierarchy of accounts (SQL Server 2012). I created a VIEW using a CTE to hash out the hierarchy, ...
10
votes
2answers
3k views

Tracking stored procedure usage

Besides using SQL Server Profiler, is there any way to track which stored procedures are being used, or at least when they were last executed?
9
votes
2answers
770 views

Hard limitation for merge replication article count?

A bit of background. We developed an app that uses merge replication. Right now, we are currently publishing about 212 articles, and everything is fine, as it appears to fall into the 256 article ...
8
votes
3answers
2k views

INSERT takes over 5 hours, when inserting more than specific number of rows

When inserting less then about 1,350,000 rows to the table it all takes about 2 minutes, however when number of inserted rows is bigger, then the time needed to insert data grows to about 5 hours. ...
8
votes
1answer
549 views

In case of multiple updates of the same record in a single transaction, how many versions are being stored?

According to MSDN article by Kimberly L. Tripp, Neal Graves's "SQL Server 2005 Row Versioning-Based Transaction Isolation "... All the earlier versions of a particular record are chained in a linked ...
8
votes
2answers
966 views

What is the meaning of DOP in the context of SQL Server?

What is the meaning of DOP in the context of sql server?
7
votes
3answers
603 views

Restricting users to COPY ONLY backups

I am looking to deploy log shipping in my production environment. This will mean I will have to manage backup chains which could be disrupted by people taking backups to refresh development ...
7
votes
4answers
11k views

Converting RTF in a text column to plain text in bulk

I have a legacy system with about 10 million rows in a table. In that table there is a column of type text, most of them are standard text but about 500 thousand rows have RTF markup in them. I need ...
7
votes
2answers
849 views

Can Availability Groups replace transactional replication?

I've been looking at the new features of SQL Server 2012, and how it can help my current situation. Currently we're on SQL Server 2008 R2, and replicate two OLTP servers' databases to a single ...