-2
votes
2answers
44 views

Index is not used with same Query on two Servers

I have two notebooks with same specs (same model, only ram is 24GB/32GB, same ssd) and exact same database and same sql server version. SQLIO is 3300 and 3600. Now I run a query on one notebook and ...
1
vote
1answer
38 views

Optimistic Paging and separate query for COUNT?

I am using SQL SERVER 2012 FETCH/OFFSET after searching a lot that this will give me the best performance. But for paging to work, I need a Total count. There are 2 ways to achieve this. 1) Paging ...
0
votes
4answers
87 views

SQL Where Clause Efficiency

Say I have a SQL statement: SELECT * FROM MyTable WHERE KeyColumn1 = 1 OR KeyColumn1 = 2 OR KeyColumn1 =3 OR ... KeyColumn1 = 10 And another: SELECT * FROM MyTable ...
0
votes
0answers
68 views

Why has the backup time significantly increased?

I'm using Sql Server 2012. The problem is that the backup takes about twenty minutes now, whereas only a few days ago it took a matter of seconds. The database has increased by about a sixth since ...
3
votes
2answers
112 views

Enhance performance of update query

I have a query that is running against a table with 50 million rows. The phone number is stored as a CHAR(10) and an ETL process is changing the phone number if it has certain values. We are seeing ...
2
votes
2answers
47 views

SQL Server 2008 R2 Missing Index

I am performing index maintenance on a database. I have run SQL script that uses DMVs to provides a list of indexes SQL Server believes should be created. I am not creating indexes just because the ...
1
vote
3answers
57 views

Is bulk-logged recovery model ever a good choice if point-in-time restore is not needed?

Is the Bulk-Logged recovery model in SQL Server ever preferable to Simple if point-in-time restore is never needed? I have read many articles about transaction log models, but cannot find a clear ...
7
votes
4answers
546 views

How do I best measure the query performance?

I have 2 stored procedures, where the second stored procedure is an improvement of the first one. I'm trying to measure by exactly how much that is an improvement. 1/ Measuring clock time doesn't ...
2
votes
1answer
139 views

Disk Latency vs Throughput

I've searched the web for a little while and haven't found an answer I'm confortable with. I am testing a SQL Server on a VM that was presented new disc. If disk latency is reduced, shouldn't ...
3
votes
1answer
91 views

Frequent Delete & Insert, impact on performance

In my application, we have very few updates. Most of the data gets deleted and inserted. My question is, how this will impact the performance? We are using SQL Server 2012. Table statistics (will ...
3
votes
2answers
178 views

High CXPACKET and LATCH_EX waits

I am having some performance issues with a data processing system which I am working on. I have gathered wait stats from a one hour peroid which show a large amount of CXPACKET and LATCH_EX wait ...
8
votes
3answers
209 views

When a previously-fast SQL query starts running slow, where do I look to find the source of the issue?

Background I have a query running against SQL Server 2008 R2 that joins and/or left-joins about 12 different "tables". The database is fairly large with many tables over 50 million rows and about 300 ...
11
votes
1answer
507 views

GO After every T-SQL statement

What is the reasoning behind using the GO statement after every SQL statement? I understand that GO signals the end of batch and/or allows the reputation of statements but what advantage does it have ...
4
votes
1answer
53 views

How can a connection for one DB block a connection to another DB in SQL Server?

We have an interesting scenario. For weeks, we have been experiencing 'outages' on SQL Server 2008 -- where our websites have slowed to a crawl and mass timeouts for all customers who have DB's ...
6
votes
1answer
215 views

Estimating IO Requirements for Bursty Usage

We have an application that queries a SQL database periodically throughout the day. There are periods of zero or only light activity, interspersed with individual requests for relatively large ...
2
votes
1answer
78 views

Avoiding Deadlocks

We currently have a trigger-based system in place that does the following: When records in certain tables are modified, a trigger fires that makes a field NULL in a varying number of records in ...
0
votes
0answers
50 views

TempDB causing high IO writes - dependent on server's max memory setting [duplicate]

I have a mirrored SQL Server 2012 database. The first server has a hugh tempdb write IO load when the maximum memory limit is set above 8192 mb. These 8192 where the original setting for both the ...
0
votes
1answer
48 views

RAID0 vs multiple files in file group

I have a server that gets updated and backed up once a day and processes queries the rest of the day (selects). I'm trying to improve performance of the update process and the selects. I'm not worried ...
6
votes
2answers
510 views

What is the fastest way to insert large numbers of rows?

I have a database where I load files into a staging table, from this staging table i have 1-2 joins to resolve some foreign keys and then insert this rows into the final table (which has one partition ...
2
votes
1answer
97 views

Specifying columns in LEFT JOIN through subquery beneficial performance wise?

I'm trying to understand how JOINS are handled, and was wondering about the following: Imagine a big query concerning a lot of tables, I'm really looking for small optimizations as it's a pretty ...
4
votes
0answers
86 views

SQL Server CPU spikes - possibly non-query related - suggested indicators

I'm looking for suggestions for indicators I could monitor to discover what is causing these cpu "blunted spikes". Some known information: sqlserver.exe is confirmed as the process consuming the ...
3
votes
0answers
161 views

Database under heavier load — all SQL queries start timing out after a period of hours/days

I make a web application which has experienced heavy growth in the past week and it appears my database is seizing up because of it. You can see that everything seemed to be OK until about 3AM this ...
0
votes
1answer
176 views

Improve Insert performance for 200 Million rows

How can the following insert statement be improved - which varies from 20mins on certain days to 70-140mins on most other days. SELECT DISTINCT od.SourceID, od.OrderID, od.OrderLineNo, ...
1
vote
2answers
68 views

Does RAM taken up Shared Memory connection counts against Max Server Memory?

I have an app that's local to the SQL Server and thus has a Shared Memory connection to it. I was wondering whether the RAM taken by the connection (including data transfers) counts against the max ...
1
vote
1answer
74 views

Partition : understanding files and file groups

We are trying to partition a large history table. Being new to partitioning, I was trying to understand the concept of files and file groups. File groups can be set up in following three ways : 1. ...
4
votes
1answer
128 views

Is ASYNC_NETWORK_IO wait type anything to worry about?

In looking at the list of sprocs that take long time to execute, one stands out as causing the most wait. However, most of that wait (81%) is ASYNC_NETWORK_IO and I know why: the sproc transfers ...
3
votes
1answer
303 views

How to improve Procedure Cache Hit Ratio?

From what I can tell Procedure Cache Hit Ratio below 95% is a problem. On my box, the values hover from 85 to 95%. How do I fix this issue? The server seems to have plenty of RAM so that ...
2
votes
2answers
96 views

Autogrowth, shrink and database performance

I have already asked some questions about Autogrowth and shrink. But I have some doubts related to it. 1)I have a database which grows about 300 MB every month. So is it best to set Autogrowth of 300 ...
1
vote
2answers
102 views

Improving a search query

I have a query for search function. Basically search function allowed user to define what they "have" and "want". Then this query will filter out all the possible result which created by other user. ...
3
votes
1answer
169 views

Why is SQL Server using a clustered index scan for a self referencing FK cascade delete

I have made an example to allow me to show what my issue is: Setup: CREATE TABLE [dbo].[Test]( [TestId] [bigint] IDENTITY(1,1) NOT NULL, [ParentTestId] [bigint] NULL, CONSTRAINT [PK_Test] ...
2
votes
1answer
61 views

Non-Clustered Index key columns to cover a variable where clause

To whoever reads this, sorry for the long question and thanks so much for your time. I'm needing some help on understanding what columns should be key/non key in the following situation, and what ...
1
vote
1answer
31 views

Do the showplan (any or all) events add more overhead than a tuning trace should have

How long (order of magnitude) do the various showplan events take to record? Also is the time these events require counted as part of the "duration" column of the corresponding SQL query?
3
votes
2answers
250 views

What can cause slow queries with low resource usage?

I am writing an application which builds a database on a SQL server. The application loads data into some staging tables, then executes a series of stored procedures which merge the staging tables ...
0
votes
4answers
127 views

Can migration from MS Access to SQL Server or … make database faster? [closed]

A company asked me to migrate their database from MS Access to SQL Server or MySQL because they think that on those engines their database will run faster. But I wonder if their problem isn't because ...
0
votes
1answer
61 views

How can it take longer to replay a captured trace than to capture it

I am attempting to use trace captures to determine how much of a performance issue was database related and how much was code related. However, the trace is taking longer to replay that it took to ...
2
votes
0answers
48 views

Identical query & instance but other execution plans & performance [duplicate]

I have 2 identical queries . One is executed with parameters, the other is executed with hardcoded values. Somehow sql server is creating 2 different execution plans for the 2 queries. The first one ...
1
vote
1answer
65 views

How to isolate that network is issue of bad query performance [closed]

I would like to know how to isolate SQL Server bad query performance is caused by NETWORK and not the SQL Server. Are there any specific tips and tricks in SSMS, wait types, or specific PerfMon ...
1
vote
0answers
61 views

What to look for in query execution plans? [closed]

Assuming the query execution is slow, I have collected the xml plan. What should I look for in the actual execution plan. What are the top 10 things I need to watch out for? I know this is a broad ...
1
vote
1answer
328 views

Lazy Writes Performance Issues

My SQL Server sometimes reports high Lazy Writes e.g. "Lazy Writes per second is 119 Writes/sec" What should I be checking to find out why this is high? What are potential causes? Thanks.
2
votes
2answers
148 views

Improve Performance -Update query with OR in WHERE

How do we improve this Update query Performance as currently it is taking 1 Minute to update 17643 Rows. Query -> Declare @date datetime = '09-Dec-2013' update #tmp_sp_abc set ...
-2
votes
1answer
70 views

Maximum dataset size for a well-performing SQL Server 2012? [closed]

We're planning a project using SQL Server 2012 for storing about a billion records over less than 50 fields. Assuming good hardware, is SQL Server up to that task? Roughly how many request/second can ...
1
vote
1answer
41 views

Patterns/Designs to help with concurrency/performance [closed]

I'm working on a SQL Server 2008 R2 DB and I'm experiencing some performance/concurrency issues with probably the main table in the DB. Problems like slow reads, deadlocks, poor performance in ...
0
votes
1answer
44 views

Suggest performance tradeoffs

I have a an inner query that needs outer query column values as input. It looks something like this CREATE TABLE TISSET( COL1 int ,COL2 int,COL3 int) INSERT INTO TISSET VALUES (1,1,1); INSERT ...
2
votes
0answers
49 views

SQL Server 2012 STIntersects

I have one table, T_PIN, with 300,000 pins and another, T_POLYGON, with 36,000 polygons. T_PIN has this index : CREATE SPATIAL INDEX [T_PIN_COORD] ON [dbo].[T_PIN] ( [Coord] )USING GEOGRAPHY_GRID ...
1
vote
1answer
70 views

Restore With Move has poor performance

As part of our regular development cycle we need to take a copy of production into development databases. To do this, we take a copy of production backups and move them to the Development Server. ...
2
votes
1answer
110 views

Performance issue with TOP (1) on a nullable column

I need help to identify the reason for a performance issue. Actually following query sits in a scalar-valued-function but that is not the reason for the issue since it needs the same time as query: ...
0
votes
1answer
51 views

SQL Server 2000 Replication, Performance, and Query Priorities

I'm a developer and wanting to confirm the following: Does anyone here have experience with SQL Server Replication (transactional) on 2000? We are trying to convince the DBAs to allow this in a ...
5
votes
0answers
249 views

SQL Server 2012 performance issues (maybe due to linked server) [closed]

Summary of the problem We've spit our one database server environment into two servers. We are now having intermittent performance issues I am hoping someone can offer clues - perhaps direction ...
-1
votes
1answer
107 views

How can I detect which indexes are being rebuilt offline and how long?

The rebuild of indexes takes appr. the same 55 min. with both "Do not rebuild indexes and "Rebuild indexes offline" "For index types that do not support index rebuilds" with "Keep index online while ...
1
vote
2answers
50 views

What does enabling containment on server incur?

Having read in a book of Patrick LeBlank "Microsoft® SQL Server® 2012 Step by Step": "Benefits and limitations of contained databases As with most features, there are benefits and ...