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).

learn more… | top users | synonyms (2)

10
votes
1answer
417 views

SQL Server 2012 Page Life Expectancy resets to 0 after about 50 days

I've noticed an odd behavior on a 2-server HA cluster and I was hoping someone could confirm my suspicion, or maybe offer some other explanation... Here is my setup: A 2-server SQL 2012 SP1 ...
9
votes
3answers
367 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, ...
9
votes
2answers
3k 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?
9
votes
2answers
581 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
386 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
1k views

SQL Server database design for “archived but available” data

We have this large database (>1TB) that we intend to "shrink". The database revolves around one main entity, let's call it "Visit". For discussion, let's say it is a database for a medical practice. ...
8
votes
2answers
4k views

SQL Server 2008 - Partitioning and Clustered Indexes

So let me preface by saying I do not have total control over my db design, so a lot of the aspects of the current system cannot be changed for the purposes of this scenario. Comments about how we ...
8
votes
2answers
2k 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 ...
8
votes
2answers
7k 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 ...
8
votes
1answer
624 views

Is there a reliable way to determine when you should run DBCC CLEANTABLE to reclaim space?

Lately, instead of just growing files when they near 80% file utilization, I've been more proactive at reclaiming space via the usual tricks like defragmenting heaps, adding & dropping clustered ...
8
votes
2answers
755 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
4answers
7k 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
557 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 ...
7
votes
2answers
507 views

Code creates different plan when ran ad-hoc vs. in a stored procedure

I have a delete statement that is using a bad plan when run inside a stored procedure, but is choosing a much better plan when run ad-hoc. I have rebuilt all the indexes for the tables used by the ...
7
votes
4answers
1k views

SQL Server: what should be done when a process is blocking another process?

I'm an accidental DBA and still learning. When I see from DMV:s or Activity Monitor that some process is blocking another process, what should be done? Should I simply kill those processes or is ...
6
votes
1answer
2k views

Transaction Log maintenance on Mirror database

SQL Server Version: 2008 R2 Enterprise SP2 I am trying to get a handle on our SQL Server maintenance and I came across something I think is incorrect. We have a single production instance with 3 ...
6
votes
3answers
7k views

Pivot rows into multiple columns

I have a SQL Server instance that has a linked server to an Oracle server. There is a table on the Oracle server called PersonOptions which contains the following data: ╔══════════╦══════════╗ ║ ...
6
votes
2answers
12k 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 ...
6
votes
1answer
245 views

How to Optimise Query

I have a database structure similar to this, CREATE TABLE [dbo].[Dispatch]( [DispatchId] [int] NOT NULL, [ContractId] [int] NOT NULL, [DispatchDescription] [nvarchar](50) NOT NULL, ...
6
votes
2answers
3k 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 ...
6
votes
3answers
2k views

Passing in the table into a stored procedure

Is it possible to pass in the name of a table into a stored procedure? For example, suppose you have several views of the same table. They all have the exact same structure. You want a store ...
6
votes
5answers
6k 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 ...
6
votes
2answers
3k views

Recover accidentally deleted rows from a table

My client has accidentally deleted all the records of a table from a test database. This test database is in SQL Server 2005 Express and we don't have a backup. Is it possible to restore the deleted ...
6
votes
1answer
688 views

Guarantee SQL Server Identity Columns that two consecutive values differ by constant increments?

I posed a question about Denali sequences here and another question about emulation of identity columns in Oracle Global Tables here. I always thought that I could trust that identity values ...
6
votes
3answers
6k views

Why is a .bak so much smaller than the database it's a backup of?

I just took a backup of a SQL Server database. The MDF and LDF files together total around 29 GB, but the .bak file was only 23 GB, about 20% smaller. My first guess when one version of a set of ...
5
votes
4answers
5k 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 ...
5
votes
1answer
3k views

How and when does SQL Agent update next_run_date/next_run_time values?

I've been working on code in T-SQL to add new schedules to a SQL Agent job using the sp_add_jobschedule proc in the msdb database. When I add a new schedule (typically a run-once at a specific ...
5
votes
2answers
2k 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
171 views

What is the correct way to ensure unique entries in a temporal database design?

I'm having trouble with the design of a temporal database. I need to know how to make sure I have only one active record for any given timeframe for a store. I have read this answer, but I'm afraid I ...
4
votes
2answers
11k views

SQL query to return a column per date in date range?

Let me explain what I've got and what I'm trying to achieve. Let's say I have Table A: BookingsPerPerson Person_Id ArrivalDate DepartureDate 123456 2012-01-01 2012-01-04 213415 ...
4
votes
3answers
3k views

Test if any fields are NULL

I'm trying to figure out an easy query I can do to test if a large table has a list of entries that has at least ONE blank (NULL / empty) value in ANY column. I need something like SELECT * FROM ...
4
votes
1answer
887 views

SQL Server: How to create a table that fills one 8 KB page?

Is there a way to calculate the amount of data that fills one 8 KB page in SQL Server and create a table that fills one page entirely? This kind of table is presented in in this blog post.
3
votes
1answer
2k views

Transaction Log Maintanance While Using AlwaysOn Availability Group

We are using HADR ( AlwaysOn Availability Group) feature of SQL Server 2012. Server and AG Configuration as below: SQL12_SRV1 --> AG1(PRIMARY) - SYNC -->> DBTest SQL12_SRV2 --> AG1(SECONDARY) ...
3
votes
2answers
339 views

Server permissions of an activation stored procedure of a Server Broker queue

I have a stored procedure that queries the sys.dm_exec_requests view. In the stored procedure the view only returns one row, while the stored procedure needs to see all of them. The MSDN article on ...
3
votes
2answers
1k views

SQL Server media belongs to which edition

Could anyone please help me on below question? Without installing SQL Server media 2008 and 2012, how can we know that the media belongs to which edition (like developer, standard or ...
3
votes
0answers
118 views

How to Audit for Access with Cross Database Ownership Chaining

I've just joined the data team of a new company and we have a large SQL Server environment (100+ instances) and cross database ownership chaining is on by what I gather is a necessity. I'm looking for ...
3
votes
1answer
4k views

Restore Backup Fails - File 'Db' cannot be restored to '{…}.mdf'. Use WITH MOVE to identify a valid location for the file

I am getting the following errors trying to do a restore using the restore command on a backup file I recieved from a customer. RESTORE DATABASE SFDB FROM DISK = N'C:\Backup\Backup.bak' Any ...
3
votes
1answer
128 views

Analysing A Query Plan

Why is the following query slow? select count(*) from [dbo].[mt_dispatch_link] , [dbo].[_mt_dispatch] [_mt_dispatch] where (mt_dispatch_link.contract_id_1 = _mt_dispatch.contract_id ...
3
votes
2answers
2k 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 ...
3
votes
2answers
6k views

SQL query that concatenate values from duplicate rows in a single table

Lets say I have a table of employees, like this: Name Sex Role Bob M Developer Joe M QA Now, I have a problem with this table of duplicated rows. I will fix it ...
2
votes
2answers
1k views

Move (Restore) SQL Server 2005 database which does not exist before

I did not ready about this but found out after trying to restore a database from remote server and it wont restore if the database did not exist before. What I would do is create a .bak file ...
1
vote
3answers
121 views

Undo SQL UPDATE Azure DB

I have accidentally updated over 3,000 records in one of my tables hosted on Azure. This was not a transaction and I did not have any back ups for this table. I've read around and found ApexSQL Log ...
1
vote
2answers
206 views

SQL 2008 Server - performance loss possibly connected with a very large table

Migrated from http://serverfault.com/questions/615129/sql-2008-server-performance-loss-possibly-connected-with-a-very-large-table We have SQL Server 2008 with 3 active databases running on it. DB1 ...
1
vote
3answers
239 views

Improve performance by partitioning

I'm using SQL Server 2012. I’m using CTE to create an orders table from the items table. The final count for the orders table is around 120 million. It is taking about 2 hours for the whole process. ...
1
vote
1answer
3k views

Set permissions on all objects for SQL users

I have a procedure that loops through all objects in the database and assigns them proper permissions to that object. I want to know if there is a better way to do this? I use a model database to ...
21
votes
3answers
4k views

Performance difference for COALESCE versus ISNULL?

I've seen a lot of people use the COALESCE function in place of ISNULL. From internet searches, I've found that COALESCE is ANSI standard, so there is an advantage that we know what to expect when ...
14
votes
2answers
526 views

Setting up a central CLR stored procedure / function respository library for internal stored procs in other databases to use?

I would like to use code that I developed in C# CLR to be used in all of the databases on the system so that I don't have to set each to trustworthy and turn CLR on and keep a bunch of the same code ...
10
votes
2answers
1k views

INT or CHAR for a Type Field

What is the best design for a table, a Type field that is of int or char(1)? In other words, given this schema: create table Car ( Name varchar(100) not null, Description varchar(100) not ...
9
votes
2answers
2k views

Unique Constraints on Nullable Columns in SQL Server 2005

In this one project I am working on, I need to set a particular field to be unique (not a problem!) but if the field is null I want the constraint to be ignored. In Sql Server 2008 I use filtered ...