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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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 ...
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2answers
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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 ...
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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 ...
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1answer
590 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 ...
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720 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?
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2answers
498 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 ...
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2answers
471 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 ...
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4answers
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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 ...
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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 ...
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3answers
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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: ╔══════════╦══════════╗ ║ ...
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1answer
239 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, ...
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3answers
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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 ...
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4answers
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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 ...
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2answers
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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
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1answer
661 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 ...
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3answers
5k 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 ...
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2answers
10k 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 ...
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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 ...
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5answers
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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 ...
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2answers
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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 ...
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3answers
2k 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 ...
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6answers
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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 ...
4
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1answer
844 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.
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1answer
122 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 ...
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2answers
251 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 ...
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0answers
110 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 ...
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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 ...
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1answer
126 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 ...
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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 ...
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2answers
179 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 ...
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3answers
198 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. ...
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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 ...
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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 ...
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2answers
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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 ...
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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 ...
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2answers
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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 ...
8
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1answer
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SQL Server nvarchar(max) vs nvarchar(n) affects performance

This is SQL Server 2008 R2 SP2. I have 2 tables. Both are identical (data and indexing), except the first table has a VALUE column as nvarchar(max) and the second has the same column as ...
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1answer
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Handling exceptions in stored procedures called using insert-exec blocks

I have a stored procedure that is called in an insert-exec block: insert into @t exec('test') How can I handle exceptions generated in the stored procedure and still continue processing? The ...
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2answers
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Why does “SELECT POWER(10.0, 38.0);” throw an arithmetic overflow error?

I'm updating my IDENTITY overflow check script to account for DECIMAL and NUMERIC IDENTITY columns. As part of the check I compute the size of the data type's range for every IDENTITY column; I use ...
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3answers
4k views

How to free SQL Server memory?

I have a SQL Server sandbox installation on my local computer. I have set the memory SQL Server instance can use to 1000 mb. When running an intensive operation, memory usage rises up to 1000 mb. When ...
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7answers
674 views

Scheduled backup task doesn't always backup all databases despite always saying job successful

I have a job in SQL 2008 that runs a stored proc to backup all databases. This runs daily via sql server agent job. It quits with success every day but some days it quits with success only after ...
7
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4answers
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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 ...
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2answers
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What is the actual behavior of compatibility level 80?

Could somebody provide me with a better insight about the compatibility mode feature? It is behaving different than I expected. As far as I understand compatibility modes, it is about the ...
7
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1answer
758 views

Why does the order of parameters matter for sp_trace_create?

The first batch of the following script calls stored procedure sp_trace_create with parameters in documentation order; the second batch swaps the positions of parameters @tracefile and @options: ...
6
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1answer
80 views

Does RCSI use less or same space than SNAPSHOT? Why?

Trying to better understand row-versioning based transaction isolations - RCSI (Read Committed Snapshot Isolation and SNAPSHOT) - in SQL Server... MSDN online article "Choosing Row Versioning-based ...
6
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2answers
222 views

Does the order of columns in a columnstore index matter?

I have a table with ~200 million rows and ~15 columns in it. I am planning to create a COLUMNSTORE index on my table. Will there be any change in performance based on the order of columns that I use ...
6
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1answer
516 views

How to back up a small database in SQL Server 2008 R2 Express Edition

I will shortly be migrating a database from SQL Server 2000 (part of SBS 2003) to SQL Server 2008 R2 Express Edition The database is small, and there are only a few hundred short transactions per day ...
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2answers
333 views

Index seek much slower with OR condition compared with separate SELECTs

Based on these questions and the answers given: SQL 2008 Server - performance loss possibly connected with a very large table Large table with historical data allocates too much of SQL Server 2008 ...
5
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2answers
688 views

Find which session is holding which temporary table

We have a SQL Server 2005 database the temp database has become full. By going into SQL Server Management Studio I can see all the temporary tables in the tempdb. Is it possible to tell which session ...
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6answers
845 views

Backup very large table

I have to update certain values of a large table (for the sake of a presumed example, it is called 'Resource' and it is over 5M rows) and thus I have to make a backup before performing the changes. We ...