An evaluation of whether a system works well enough to be fit for purpose. Normally performance refers to the speed with which a system completes an operation or set of operations over time.

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87
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7answers
84k views

How can I optimize a mysqldump of a large database?

I have a symfony application with an InnoDB database that is ~2GB with 57 tables. The majority of the size of the database resides in a single table (~1.2GB). I am currently using mysqldump to ...
3
votes
1answer
3k views

To 'DBCC SHRINKDATABASE' or Not To 'DBCC SHRINKDATABASE': That's the question

We're freeing lots of space in a SQL Server 2008 R2 database -a Loooot! enough to care about- (we're dropping lots of unnecessary data). but the database file conserves its file size. we want to ...
0
votes
3answers
1k views

SSIS 2008 painfully slow to import CSV

I am using SSIS to import a 25,000 row CSV to an empty table. The table has a primary key that is populated as the data is inserted. I am using an ADO.Net destination. What reasons are there why ...
1
vote
2answers
300 views

What is wrong in debunking myths about clustered indexes?

What is wrong in code. or its results, illustrating that clustered index is evil [1]? and how to de-debunk, i.e. to return to customary myths and best practices? [1] Debunking myths about ...
4
votes
2answers
251 views

SQL Filegroup degrading performance

On our dev boxes, our database resides entirely in the PRIMARY filegroup, and everything works fine. On one of our production servers, recently upgraded from 2005 to 2008, we noticed it was ...
11
votes
3answers
5k views

SQL Server - Temporary vs. Physical Tables

A movement is afoot in my place of employ to move away from using #temp tables and instead to use permanent physical tables with SPIDs. Whenever one would have previously INSERTed INTO a #temp table, ...
7
votes
3answers
6k views

Performance Hit using CAST() in TSQL (SQL Server)?

We have a SQL generator that emits SQL conditional statements generically for specified fields (which for the sake of discussion: we will label as myField). So, if myField is of type NVARCHAR, we ...
7
votes
1answer
114 views

Is there a performance hit by breaking out tables into different schemas in SQL Server?

Is there any kind of performance hit when querying by placing tables in different schemas in SQL Server. For instance if I had 2 tables, Table1 and Table2, and put Table1 into the test schema and ...
1
vote
3answers
296 views

Is there an equivalent of “OPTION(RECOMPILE)” or “WITH RECOMPILE” for an entire connection?

I'm curious. Is there any way to prevent SQL query execution plans from being cached for an entire connection's duration? Can I run a command that basically says, "use OPTION(RECOMPILE) for all ...
2
votes
2answers
68 views

query plan caching (sql server)

Is there a measure of time frame as to which the execution plan of inline queries will cached?
2
votes
4answers
482 views

Help understanding SQL Server 2005 execution plan

One of my stored procedure has long execution time (average around 4 to 7 minutes). Now I trying to tweak it an make it run faster. I am looking at execution plan and two things I see that using ...