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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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
1answer
530 views

Allow non-sys admin, non-owner of a 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 ...
4
votes
1answer
253 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
6answers
7k views

SQL Server log shrinking Issue [duplicate]

Possible Duplicate: Why Does the Transaction Log Keep Growing or Run Out of Space? I have a 300 GB database log in our SQL Server. I want to shrink all the logs but it is not allowing me to ...
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
959 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
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1answer
3k 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
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1answer
1k views

SQL Server Many-to-One replication

I have 8 individual SQL Server 2008 R2 machines, each hosting 1 database. Each database has an identical table structure and schema, and entirely unique data. I would like to establish a reporting ...
3
votes
2answers
425 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
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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
124 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
6k 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
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1answer
132 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
3k 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
8k 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
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1answer
3k views

Migrating from SQL Server 2005 to SQL Server 2008 R2 on a different box

We currently have a SQL Server 2005 instance hosting a lot of application specific databases (ArchiveManager, SolarWinds, Kaspersky etc). We are planning to deploy a new SQL Server 2008 R2 instance on ...
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
166 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
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2answers
227 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
292 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
4k 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
5k 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
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2answers
558 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
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5answers
2k 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 ...
10
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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 ...
9
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4answers
3k 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 ...
9
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3answers
3k views

Restrict access for Windows administrator

As the SQL Server best practices says, "Windows Authentication mode is more secure than SQL Authentication". And now I want to know: is there a way to protect SQL Server from user with Windows ...
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 ...
8
votes
1answer
4k views

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 ...
8
votes
1answer
5k views

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 ...
8
votes
2answers
4k views

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 ...
8
votes
3answers
5k 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 ...
8
votes
7answers
795 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
votes
1answer
1k views

Do schema changes “break” SQL Server 2012 AlwaysOn or are they handled transparently?

My organization is planning to adopt SQL Server 2012 AlwaysOn and I am trying to understand what impact (if any) it will have on our application upgrade process. We release application updates on an ...
7
votes
1answer
896 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
votes
4answers
890 views

Does SQL Server ever delete old error log files?

I know I can cycle the current error log easily by running sp_cycle_errorlog, but I'm wondering if SQL Server will ever delete the old/archived error log files at all. Can't seem to find an answer to ...
6
votes
1answer
102 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
votes
2answers
1k views

How can I save a severely fragmented database/table?

I've recently made a discovery that might explain my slow SQL run times. I found out that the default in SSMS is to allow mdf growth of 1MB at a time. When the size of one table alone is roughly 23 ...
6
votes
2answers
277 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
votes
4answers
5k views

Can I be automatically notified of prolonged blocking in SQL server?

About once a week I have to resolve a blocking chain on a SQL Server 2005 database, caused by a long-lived read lock from an Access 2003 front-end. The lock is taken out whenever a user opens a ...
6
votes
1answer
541 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 ...
5
votes
1answer
204 views

How do I track logins, connections, user accounts, queries, …?

I am a BI person who has been asked to step in and pretend I am a DBA. I am not a novice with databases but AM a novice at the admin type stuff. We have a SQL Server database that is going to be ...
5
votes
2answers
402 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
votes
1answer
1k views

Insert with OUTPUT correlated to sub query table

I am modifying the structure of a database. The content of several columns of the table FinancialInstitution has to be transferred into the table Person. FinancialInstitution is linked to Person with ...
5
votes
3answers
309 views

How do I find all tables in a DB that have no explicit primary key?

A Google search spewed forth millions of hits on how to find tables without clustered indexed, the PK normally being the clustered index of a table. However, a table could easily have a natural key as ...
5
votes
2answers
3k views

When to make changes to the cost threshold for parallelism

While examining a performance issue , I have seen an influx on CXPACKETS suggesting I might need to look at the cost threshold for parallelism and perhaps the MAXDOP. Before making any drastic ...
5
votes
6answers
2k 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 ...
5
votes
3answers
16k views

SQL Server Restore a SINGLE table from a backup [duplicate]

on SQL Server 2005, we do a weekly full backup with nightly incremental backups. I want to know if it is possible to restore a single table from a backup, either to the source database or a ...
5
votes
1answer
386 views

How does SQL Server order results when joins are used?

How does SQL Server figure out the order of the records in the result set of query execution? I am trying to make heads or tails of it but find myself scratching my head. When I change the fields I ...
5
votes
3answers
2k views

SQL Server virtual log size

I'm somewhat of an accidental DBA, being a developer who inherited a couple of database servers (2005 and 2008) from someone who knew little about database administration, and seemingly had even less ...