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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Is it possible to backup and restore part of a database in sql-server?

We have a sql-server 2005 database that we regularly transfer from our client site to ours. This takes a long time because we don't have a direct connection and have to transfer the file over their ...
6
votes
2answers
1k views

How to backup/restore SQL Server database from command line similar to mysql

I need to automate the migration for some databases from an older server. I know that script a tool using C# for example can be a possibility but I need a simple, fast and effective solution in order ...
4
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3answers
2k views

NULLs in a composite primary key - SQL Server

I'm trying to work out the best way of creating SQL Server primary keys, foreign keys and constraints to accurately represent my data model in LINQ / Entity Data Objects. Let's assume - for the ...
3
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4answers
1k views

Query to find GUID's “not in” null containing subquery returns no results

When I have a query that checks if a column of type uniqueidentifer does not exist in a table that has a null value then I get no results back. If the subquery does not return a null it works fine and ...
3
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1answer
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Running queries with SQLCMD vs. Running queries with SSMS

I've noticed something which i'm not sure about. can it be that running queries directly with SSMS is much faster than running queries with SQLCMD? I've noticed that the results of queries that ran ...
3
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2answers
756 views

Restore a Database into a Current Database and merge

I want to know how, or if it is possible, to backup a database then should the user wish, restore that database at a later date and merge it with the one they are currently using. Both Databases will ...
3
votes
1answer
341 views

Shrinking log file

Some of the sql log files (idf) are hugh like 5gb. Found a article (http://extended64.com/blogs/rhoffman/archive/2009/06/11/shrink-sql-server-2008-database-log-file-script.aspx) but not sure why he ...
3
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1answer
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Is SQL Server Backup single or multi-threaded?

If you perform a... BACKUP DATABASE [DB_Name] TO DISK=N'c:\backups\db_name.bak' WITH STATS=10 Will that perform a single or multi-threaded write? Our Server support company advised us that if we ...
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3answers
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SQL Server 2008 R2 High memory usage

I have SQL Server 2008 R2 that runs multiple jobs over night, the problem is SQL Server will eat up all RAM and CPU, then it will not release the RAM resources after the job finishes, as a workaround ...
1
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1answer
198 views

routine to backup ssas databases fails with: The XML for Analysis request timed out before it was completed

I have developed my own stored procedure, that through a LINKED SERVER, backups the SSAS databases according to a table value parameter. the code for the stored procedure is below. the problem: it ...
1
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1answer
213 views

Restoring a differential backup in SQL server 2005

I have created a full back up of my database by executing the line below in my application: Dim Query As String = "backup database Ari to disk='G:\Documents and Settings\i\Desktop\BKAR\" & ...
1
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1answer
962 views

Conversion of varchar data to datetime failing

We are in the process of moving data from a legacy table (all varchar fields) into a strongly typed counterpart cue cheering As part of this effort, we are taking data from the base Entity table and ...
0
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1answer
4k views

How to copy backup files to remote share in SQL Server Agent job without AD/domain accounts involvement?

MS SQL Server 2012... with nightly databases backups to the same/local as SQL Server machine... I am trying to add another SQL Server Agent Job to copy the .bak files to remote (non-windows, i.e. ...
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votes
1answer
561 views

Why does a VIEW with a CLUSTERED index not use the index?

I have a view that has a clustered index along with other non-clustered indexes. A simple SELECT query does not use any of the indexes even when I select an indexed column. What could be the ...
27
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3answers
19k views

What risks are there if we enable read committed snapshot in sql-server?

I have read here that some extra data will be stored per row so we might see a performance degradation but what other risks are there? eg. Will this affect recovery of the database? Is there anything ...
14
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2answers
7k views

What are the best practices for running SQL Server in a Virtual Machine?

What are the best practices for running SQL Server in a Virtual Machine? My on-line transaction activities are very low, but there is a high amount of data processing for the purpose of providing ...
31
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2answers
73k views

How to the get current date without the time part

In SQL Server 2005 how do I get the current date without the time part? I have been using GETDATE() but would like it to have a time of 00:00:00.0
16
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2answers
3k views

Handling growing number of Tenants in Multi-tenant Database Architecture

Handling a modest number of customers (tenants) in a common server with separate databases for each tenant's instance of the application is relatively straightforward and is normally the correct way ...
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11answers
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How can I track database dependencies?

As internal applications evolve over a number of years, you occasionally find there are a number of tables that people believe are no longer relevant and want to cull. What are the practical methods ...
25
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7answers
5k views

What is the difference between a “record” and a “row” in SQL Server?

There was a rather innocuous question about adding dates and times in SQL Server that set off a rather fascinating taxonomic debate. So how do we differentiate between these related terms and how we ...
13
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6answers
9k views

Optimal drive configuration for SQL Server 2008R2

I have a fairly busy database server running SQL Server 2008 R2 that has the following setup: SATA RAID 1 (2 Drives) - OS / Programs SAS RAID 10 (4 Drives) - Sql Database Files (data and logs) SAS ...
13
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4answers
3k views

Identifying Unused Stored Procedures

This next year, I am helping an effort to clean several SQL Server environments. We have about 10,000 stored procedures and estimate that only about 1000 of them are used on a regular basis, and ...
20
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7answers
28k views

How can I tell if a SQL Server database is still being used?

We're looking to decommission a SQL Server instance which has a couple databases still remaining on it. How can I tell if they are still being used by users or a web application? I found a forum ...
17
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3answers
6k views

Running total with count?

As the title suggests I need some help getting a running total in T-SQL. The problem is that the sum I need to do is the sum of a count: sum(count (distinct (customers))) Say if I ran the count ...
16
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1answer
6k views

Connection pools being reset with Error: 18056, Severity: 20, State: 46. & Perfmon Counters not showing

We are using SQL authentication & .net 4.0 Connection strings to connect to an Enterprise Edition 2012 SP1 SQL Server on a windows 2008r2 Enterprise Server. We use about 50 Servers split into 8 ...
12
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2answers
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High Disk I/O from sql server or is High disk I/O slowing sql server?

I've been arguing with a DBA and a couple hardware guys about performance issues on our SQL server. Normally everything is fine, however over the past few weeks we have been having huge lag spikes in ...
21
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2answers
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Why does query error with empty result set in SQL Server 2012?

When running the following queries in MS SQL Server 2012 the second query fails but not the first. Also, when run without the where clauses both queries will fail. I am at a loss why either would fail ...
18
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1answer
5k views

Why is using a table variable more than twice as fast as a #temp table in this specific case?

I was looking at the article here Temporary Tables vs. Table Variables and Their Effect on SQL Server Performance and on SQL Server 2008 was able to reproduce similar results to those shown there for ...
15
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2answers
2k views

Why does DELETE leave a lingering effect on performance?

At the end is a test script for comparing the performance between a @table variable and a #temp table. I think I've set it up correctly - the performance timings are taken outside of the ...
15
votes
2answers
20k views

How to find the SQL statements which caused the tempdb grew huge?

The tempdb of an server (SQL Server 2008) increases to 500+G several times every month. Is it possilbe to find out which SQL statements cause the problems? (The problem is usually not caused by create ...
11
votes
1answer
5k views

Trigger in combination with transaction

Suppose we have the following situation: We have a table (let's say Table_A), wich has a trigger on INSERT. The trigger job is to update some rows in table_B based on the inserted values in table_A. ...
5
votes
4answers
5k views

SQL Server - Separating data, log, and TempDB files on a SAN

I have a SQL Server connected to a SAN. Our new storage vendor recommends that all LUNs span the entire disk array, which is RAID5. I would normally request 3 separate LUNs (data, log, and TempDB) ...
11
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3answers
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SQL Server Agent Jobs and Availability Groups

I'm looking for best practice in dealing with scheduled SQL Server Agent jobs in SQL Server 2012 availability groups. Maybe I missed something, however at the current state I feel that SQL Server ...
8
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2answers
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SQL Server Join/where processing order

After reading Slow SQL query, not sure how to optimize, it got me thinking about the general performance of queries. Surely, we need the results of the first table (when other tables are joined) to be ...
6
votes
3answers
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SQL Server Primary key / clustered index design decision

Looking for some advice regarding a table / index design decision I've got to make on some tables that I've got to port into SQL server from an existing 4GL based database. I've got a product history ...
4
votes
2answers
3k 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 ...
13
votes
2answers
2k 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 ...
8
votes
3answers
673 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 ...
8
votes
5answers
1k views

Inclusion of ORDER BY on query that returns no rows drastically affects performance

Given a simple three table join, query performance changes drastically when ORDER BY is included even with no rows returned. Actual problem scenario take 30 seconds to return zero rows but is instant ...
6
votes
2answers
2k views

Is there a better option than Union All for multiple selects from the same row?

Example Schema: CREATE TABLE [dbo].[Base]( [ID] [int] IDENTITY(1,1) NOT NULL, [Option1ID] [int] NULL, [Option2ID] [int] NULL, [Option3ID] [int] NULL, [Option1Name] [varchar] NULL, [Option2Name] ...
5
votes
4answers
25k views

High CPU usage on SQL server - Slow queries [closed]

Our MS SQL Server is using about 95% of the CPU-power. After a server (hardware) restart, or a SQL-Service restart, the usage is 0% and slowly increases over the course of 1-3 days. Depending on how ...
17
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 ...
13
votes
3answers
8k 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 ...
11
votes
2answers
8k 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 ...
11
votes
4answers
3k 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
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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?
10
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1answer
591 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
4k 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, ...
10
votes
4answers
3k views

What tools are there to generate test data for SQL Server?

As you can see from another question of mine, generating test data is my theme right now. At this point, I'm still generating my test data by hand. However, this process always generates small ...
9
votes
3answers
1k views

PostgreSQL Initial Database Size

There are 2 parts to my question. Is there a way of specifying the initial size of a database in PostgreSQL? If there isn't, how do you deal with fragmentation when the database grows over time? ...