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4
votes
1answer
5k views

Large table and poor performance - what to do next?

We have a Windows 2008 R2 / SQL Server 2008 R2 (Standard) server that is used to host a single database. The database itself mainly consists of a single large table containing both live and historical ...
0
votes
2answers
596 views

Drop a SQL Server database

Taking too long to drop a 500gb+ SQL Server database. My question being what ways can we drop a database other than through GUI or T-SQL? Would deleting the .mdf and .ldf files from the server help? I ...
3
votes
1answer
2k views

Restoring database to UNC path on local drive

When I try to restore a database using a restore command with a local UNC path: RESTORE DATABASE [dbname] FROM DISK = N'\\PC91\D\backup.BAK' WITH FILE = 1, MOVE N'test' TO N'\\PC91\D\dbname.MDF', ...
1
vote
1answer
193 views

Suppress repeated performance condition alerts

I have set SQL Server performance condition alert with details as follows: Object : SQL Server:Databases Counter : Percent Log Used Instance : My database name Alert If ...
4
votes
1answer
739 views

Is there any interruption of service when switching recovery models?

I need to switch to FULL recovery model for several SQL Server 2008 databases. However these are in production. Whilst doing these things out of hours is good practice I wanted to plan for any down ...
3
votes
2answers
488 views

Need to change alphanumeric characters to next character

I have 2 columns Name, Passport No. in a table with more than 100k rows. Name Passport No. KOP A245 COS C990 After the update it should look like this. Name Passport No. LPQ B356 DPT ...
12
votes
2answers
30k views

How to partition an existing non-partitioned table

I have an existing table with data: dbo.Test (col1,col2,col3....) ON [PRIMARY] I need to change this table to be partitioned like this: dbo.Test(col1,col2,col3....) ON Ps_Date(Col2) How I can I ...
3
votes
1answer
174 views

Conversions between any data type and the binary data types are not guaranteed to be the same between versions of SQL Server

I just found that on the SQL Server 2012 MSDN documentation for binary and varbinary types, they mention the following at the end of the article: Conversions between any data type and the binary ...
8
votes
3answers
1k views

Updating a big replicated Dimension (SQL Server PDW)

We use a SQL Server PDW appliance for our data warehouse. One of the tables in our warehouse is a replicated table with about 20 million rows. As part of our ETL process we need to expire old records ...
3
votes
1answer
1k views

Are passwordless logins like ##MS_SQLResourceSigningCertificate## , ##MS_AgentSigningCertificate## a vulnerability?

I'm new to MS SQL Server. Colleagues working in IT security, have run an scan showing come DB users with null password. Some of them are ( # included ) ##MS_SQLResourceSigningCertificate## ...
4
votes
2answers
711 views

Create a new database in SQL Server 2008 R2, but it is not Blank

When I try to create new database in SQL Server 2008 R2, it was created completely, but it is not a blank and empty database, there are many tables that come from another database. I also tried ...
3
votes
1answer
251 views

Mathematical method for spotting irregularity in numbers flow

I am trying to build an engine which is going to predict orders for items inside shop. Three main variables are: Time-dates (x-axe etc 1.1.2013,1.2.2013 etc I do calculation one per day) Available ...
4
votes
0answers
290 views

SQL Server insert randomly takes 10+ seconds to complete? [closed]

I have an insert statement that is being generated by the .NET Entity Framework. In most cases, this particular insert will execute in 0ms according SQL Server Profiler. One out of every 30 or so ...
2
votes
1answer
79 views

Defining a process for troubleshooting performance issues [closed]

The issue of poor database performance is one which presents itself from time to time and there are many techniques which can be employed to examine the root cause of slowness. Does anyone have a ...
3
votes
1answer
171 views

Replace column values?

I recently got into SSIS and haven't been able to find what I am trying to achieve anywhere on the web. I am trying to take some rows as input, and then replace one specific column's value with ...
7
votes
1answer
313 views

Auto Update Statistics Duration and Interruptions

Our production SQL Server 2008 R2 sometimes begins to perform slowly: all queries begin to work too slow (and sometimes all queries just hang and wait something then continue). This usually lasts ...
2
votes
2answers
4k views

scramble the value of one column and unscramble it?

I want to change all the values in one column, as it is a production database and I don't want to give the data to testers without obfuscation. Example: Name Name ---- --> ...
2
votes
1answer
585 views

Grouping over multiple data dimensions (pivot)

I am logging an Events table, and want an output (as seen at the bottom of this answer), the issue is that I am getting the data in rows, but want them to be displayed column-wise. The two dimensions ...
3
votes
1answer
577 views

How to track overhead of Change Tracking in SQL Server

We're going to implement a solution based on Change Tracking feature from SQL Server. Before going in production (even after), we'd like to keep track of the overhead the CT will introduce. Once in ...
0
votes
1answer
3k views

LEFT vs CHARINDEX for matching the start of a string in T-SQL

I want to match the beginning of a string in a WHERE clause. While I recognise that so often database-performance is dependant on the underlying data structure, is there a best-practice for doing ...
9
votes
1answer
2k views

How important are transaction log VLFs for performance?

How important are VLFs when considering database performance? What would describe an optimal situation for VLFs?
6
votes
2answers
527 views

Should I add a column or 1-1 table if property is usualy null

There's a new unique property we need to add, which is relevant only to a specific subset (less than 1%). We thought it's better to add a new table which will be 1-1, than to add a new column which ...
10
votes
1answer
10k 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 ...
2
votes
1answer
113 views

Using queries instead of loops to modify database principals

I need to check for the existence of certain users on some database servers, each of which has over 1,000 databases, and create the users if they don’t exist and assign proper database roles to them. ...
3
votes
4answers
2k views

Replication fails because of a non-existent foreign key

I have been trying to get a previously working replication to start working. I have tried many settings, but I can't seem to make it work. Here is the scenario. I dropped all the FK constraints ...
4
votes
2answers
9k views

Possible to run multiple Reporting Services (SSRS) instances on different machines with databases on same machine?

With SQL Server 2012, can SSRS instances be setup on two different machines, with both instances using the same machine for their SQL Server databases? Machine 1 SQL Server 2012 Database Server ...
5
votes
2answers
3k views

Disk Space Considerations for Rebuilding a large Clustered Primary Key Index

We have a table in our database with over 200 million rows and a Clustered Primary Key Index which is over 100GB. The Primary Key is only so large because many more millions of rows have been archived ...
4
votes
1answer
735 views

Locking in “Read Committed Snapshot”

If an update is run on a table with "Read Committed Snapshot" isolation level and a commit is pending eg: update table1 set col1 = col1 + 1 where PKcol < 3 update table1 set col1 = col1 + 1 ...
2
votes
2answers
112 views

Read committed snapshot:Finding lock on table

IF update command is run on a table and commit is pending then another user cannot be able to update the table. Is there any query to get the user or PC which caused lock on the table.
3
votes
1answer
2k views

Does the Binary Data column shown in SQL Profiler contain useful information?

Many of the events that SQL Profiler captures include a Binary Data column. The documentation for these event classes merely repeats the fact that this column contains "Binary value dependent on the ...
6
votes
3answers
2k views

Domain group as single login, but still many different database users?

We want to use Windows Authentification on SQL Server 2008 within Active Directory. Is it possible to use an AD Group as a LOGIN to the server, but then to map the actual AD USER to a database user? ...
3
votes
1answer
986 views

Distributed - across multiple databases or servers - Transactions

I have some doubts related to transactions in SQL. I perform below steps. Connection 1 open for DB1 database Begin transaction for Connection 1 Run the commands on Connection 1 Connection 2 open for ...
20
votes
7answers
15k views

How to query a database for empty tables

Due to some 'developers' we had working on our system we have had issues with empty tables. We have found that during the transfer to the cloud several tables were copied, but the data in them ...
16
votes
4answers
969 views

Execution plan vs STATISTICS IO order

SQL Server graphical execution plans read right to left and top to bottom. Is there a meaningful order to the output generated by SET STATISTICS IO ON? The following query: SET STATISTICS IO ON; ...
0
votes
3answers
1k views

Indexing for query containing xml column

I have below queries which performs little slow.So i am planning to create index.I created primay xml index and now performance improved little bit(by looking at execution plan) .Queries are shown ...
4
votes
1answer
518 views

SQL Server DR, mirroring or virtualise and mirror

I have a client with a small business server 2008 Premium installation. This obviously includes SQL Server 2008 standard on a separate 2008 server. On the SQL we run several line of business ...
3
votes
1answer
3k views

PAGELOCK Conversion Deadlock From Update to Intent Exclusive

A customer of ours is experiencing frequent deadlocks. The deadlocks are mostly on the same UPDATE statement. The deadlocks follow a pattern in which both SPIDs have acquired an update (U) lock on a ...
11
votes
1answer
16k views

When is a Dynamic Port “dynamic”?

I was having a discussion today about Dynamic Ports with one of my co-workers and could use some help clarifying how they work. First question: If the IPALL TCP Dynmaic Ports setting is a specific ...
4
votes
4answers
6k views

SQL Server Min Server Memory

using SQL 2008 R2 with SP2 with a server with 64 GB of RAM. I have set max server memory to 58GB considering SQL Server is limited to only database engine related service only. I have a question ...
0
votes
1answer
4k views

Cannot create an instance of OLE DB provider “OraOLEDB.Oracle” for linked server

i am having a bit of a linked server problem . I created a sql server linked server and it's been working fine for last 2 years and suddenly not working . SQL Server Microsoft SQL Server 2005 - ...
3
votes
3answers
878 views

Simple XML .query SELECT statement times out on 1 SQL SERVER instance

I dropped and recreated a stored procedure on a DB on a SQL Server 2012 instance (SERVER1/INSTANCE1), after which the sproc started hanging on a line. Using profiler I have reduced a recreateable ...
1
vote
0answers
1k views

Linked server error when querying one table

I am running 2 queries using the same linked server. SELECT * FROM [SERVER].[Customer].[dbo].[ccr_AxCust1] SELECT * FROM [SERVER].[Customer].[dbo].[ccr_AxCust2] For Query 1 this returns results ...
0
votes
2answers
557 views

“an agent job has not been created for this subscription”

I have set up merge replication with a publisher on my SQL Server 2008 R2 box with the distributor on this box too; in Express I have created a subscriber but the subscriber won't run because of the ...
2
votes
2answers
224 views

Is there really any benefit in wrapping random ad-hoc queries in a transaction?

I am no db expert, but I was very surprised when someone working at our client's company asked us to send all queries wrapped in a transaction like below: SET TRANSACTION ISOLATION LEVEL READ ...
-1
votes
1answer
1k views

Totals Column - Blank if Zero or NULL

A report currently computes a "totals" column like so: ,CASE WHEN ISNULL(CLM_BREAKFAST_TYPEA.MealsA, 0) + ISNULL(CLM_BREAKFAST_TYPEB.MealsB, 0) = 0 THEN '' ...
3
votes
1answer
1k views

Displaying Parent Child Information, With Certain Parent Columns Only Shown Once

For a TSQL report, I have a one-to-many parent-child relationship. I want to report both parent and child relationships in the same report, like so, with the parent columns on the left and child ...
3
votes
2answers
3k views

SQL Query too slow on SUM function

I've a table with around 32 million rows having clustered unique index on CountryID,RetailerID,ProductID,DateID,EventID,TypeID and query is SELECT f.RetailerID , TypeID ...
2
votes
1answer
232 views

CTE query doesn't print the right structure?

I have this table which represents hierarchy : childID parentID NAME siblingOrder 1 1 a 0 212 1 ab 1 112 ...
1
vote
1answer
600 views

Selecting from an excel spreadsheet into SQL Server table

This question has been asked before but I tried giving full admin rights to the SQL Server user on C:\temp\ folder location (I am using Windows authentication into SQL Server Express). So for the ...
2
votes
1answer
4k views

Permissions using .NET SqlDependency

SQLDependency Notifications work fine logged in as Windows Domain User, using Trusted Connection. But not as SQL-User: I created a db login, user and role as follows: CREATE LOGIN myLogin WITH ...