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 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 ...
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3answers
249 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 ...
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5answers
8k 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
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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 ...
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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
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1answer
3k 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
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3answers
195 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
3answers
18k 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: ╔══════════╦══════════╗ ║ ...
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2answers
24k 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
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1answer
19k 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 ...
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4answers
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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
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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 ...
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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
3k 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
627 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
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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 ...
0
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2answers
191 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 ...
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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 ...
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5answers
7k 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 ...
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2answers
7k 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?
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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
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 ...
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1answer
1k 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 ...
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3answers
744 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, ...
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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?
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2answers
755 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 ...
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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
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1answer
528 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 ...
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2answers
941 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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3answers
584 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
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2answers
821 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
661 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
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4answers
2k 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 ...
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2answers
664 views

Is there a limit to how many credentials SSMS can remember?

Using SQL Server Management Studio that came with SQL Server 2008 R2, I make connections to the same server using a number of different sets of SQL Server Authentication credentials. On my development ...
6
votes
2answers
4k 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
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1answer
258 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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votes
4answers
5k 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
2answers
295 views

Automation of backups of Large Number of Database

In a multi-tenant web application where a database is set up for each tenant, the database can be backed up and restored manually through a fairly conventional approach. I am considering this type of ...
6
votes
2answers
4k 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 ...
5
votes
1answer
462 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 ...
5
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1answer
1k 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.
4
votes
1answer
25k views

Converting a VARCHAR to VARBINARY

I've been keeping a log of expensive running queries, along with their query plans, in a table to allow us to monitor trends in performance and identify areas that need optimising. However, it's come ...
4
votes
2answers
2k views

Should I pause Mirroring and stop SQL Server services before running windows updates?

I am running Windows update on my SQL Servers (which are in a Principal-Mirror partnership, in High Safety mode). I am starting with updating the mirror and I was wondering, to increase safety, ...
4
votes
0answers
134 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 ...
4
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6answers
10k 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
5k 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 ...
3
votes
2answers
21k views

How do I find a long running query with process ID, process name , login time, user , start time and duration?

Can anyone help me to find a below given details for long running query. ProcessID, process name, database, host ,user ,process login time, query start time and query duration. I am looking for a ...
3
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2answers
1k views

Missing Transaction log in chain, Possible to skip

We have had one of our clients SQL Servers crash and need to restore it to the most recent possible time. We have a full backup from Monday and transaction logs that run every hour up until this ...
3
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1answer
5k 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) ...