sql server varchar max performance

consider just using the VARCHAR, CHAR, a nd TEXT data type, provided the characters your application uses Can be represented using the 1 byte–256 character set. By using the Non-unicode data types, you'll use half the disk space for each character-based column. If you store lots of character data then your disk space consumption savings using non-unicode characters could is Substan Tial. I converted one of our databases from using all Unicode data ty

A common performance counter for SQL Server servers, in this flag. Performance object Counter Description Processor %processor time%privileged time Recommended value: lasts less than 80Recommended value: lasts less than 10 System Processor Queue Length

There should be different filegroups in the database before the partition table is created;Assuming the database name is Df17datapro, create the user table UserID, put the first 500,000 data in the primary filegroup, place the 50~100 in the FG1 filegroup, and put more than 100 in the FG2 filegroup1. Add File group Fg1,fg2ALTER DATABASE Df17datapro ADD FILEGROUP FG1ALTER DATABASE df17dataproadd FILEGROUP fg22. Adding files to a filegroupALTER TABLEDf17dataproADD FILE(NAME=Df17datapro1,filename=

= 'white'Indexes created on the following columns will be useful to the optimizer.Au_lnameAu_lname, au_fnameThe indexes created in the following columns will not play a good role in the optimizer.Au_addressAu_fname, au_lnameConsider using narrow indexes on one or two columns. Narrow indexes are more effective than multi-index and composite indexes. Use a narrow index on each pageThere will be more rows and fewer index levels (relative to Multiple indexes and composite indexes), which will promo

SQL Server query performance optimization analysis transactions and locks (2 ). Step 1: Execute Example 2 and Example 3 code in the query analyzer. (This is the example in the previous article SQLSERVER query performance optimization analysis transactions and locks (2) -- Example 2 6 is locked by 53

Tags: instance default help input extern data package MSDN One fixOriginal: SQL Server performance Tuning resource waiting network I/OI. OverviewThe main wait for network I/O is async_network_io, when SQL Server returns a data result set to the client, the result set is popu

Tags:. sql BSP Logical str style BST cas wait tabAnnotated Source:http://www.cnblogs.com/xunziji/archive/2011/07/27/2118063.html --Begin CPU analysis optimized for related SQL --Use the DMV to analyze the statements in which SQL Server has accumulated the most CPU resources since it was started. For example, the foll

SQL Server query performance optimization and analysis of transactions and locks (1) Step 2: analyze the locking status using SQL statements. sys. in the sysprocesses view, find out the source of waiting for the initial lock of resources and the subsequent processes to be forced to stop. The following code is applicabl

, generally believed that the closer the data from the method efficiency higher. With a careful use of cascading deletes and cascading updates, cascading deletes and cascading updates as new features of SQL SERVER 2000, are reserved in 2005 and should be available. I'm talking about caution here, because cascading deletions and cascading updates have broken through the traditional definition of foreign keys

Label:Source code files 1, what is a performance issue? If the existing resources do not reach the maximum throughput, the system cannot meet the reasonable expected performance, then it can be defined as a performance problem. Performance metrics include: response time, throughput, scalability. 2, a preliminary stud

Many enterprises also use various versions of Windows 9x in various contexts, so in order to use SQL Server 2000 in these environments, we must first understand the performance and limitations of Windows 9x. Client software SQL Server 2000 client software is included with

N a long time ago, I read the technical insider's section on CPU analysis. I wrote one article, but before I finish writing it, I have something to do. Later I thought I had published it. I saw it in the draft box today. I sorted it out and published it... The Analysis of CPU utilization focuses on CPU bottlenecks, compilation, and decompilation. 1. CPU bottleneck You can check the Processor: % Processor Time counter in PERFMON to determine whether there is a hard bottleneck. If the value 1 is t

In this article I would like to summarize the following SQL Server 2014 introduces a variety of amazing performance improvements!!Cache Pool Extension (buffer pools Extensions)The idea of a cache pool extension is simple: Store page files on very fast storage, such as SSD drives, to extend the cache pool. Cache pool extensions are very handy, and if you can't add

change the original table to the online table has been modified failed. After you temporarily disable SQL Server account, you can modify the name of the table.Analysis: There is a schema-stable lock during SQL execution, and it is easy to modify the data structure failure for highly concurrent access tables. It is recommended that you temporarily stop the busine

Label:I believe a lot of friends, whether it is to do development, architecture, or DBA, are often heard of the word "tuning". Talk about "tuning", may make a lot of technical staff heart passion, also may make a lot of people feel distressed, do not know how to start. Of course, there are many people who are dismissive of this, because not everyone does the project is very high performance requirements. In the mainstream of enterprise-level developme

SQL Server database Performance optimization SQL statement text address: http://www.blogjava.net/allen-zhe/archive/2010/07/23/326927.htmlPeriod project needs, did a period of time the SQL Server

SQL Server database performance optimization http://www.blogjava.net/allen-zhe/archive/2010/07/23/326927.htmlRecent project needs, did a period of time SQL Server performance optimization, encountered some problems, but also accum

Extending a SQL Server environment across multiple systems can be said to be a difficult and complex project, involving partitioned databases, federation, and so on. So, when it comes to SQL Server scalability, most organizations prefer to take the approach of extending independent systems before trying to solve them.

SQL Server database mirroring key Performance countersThere are 5 basic methods of monitoring database mirroring:1. Configure the database Mirroring Monitor, set the alarm threshold value.2. Configure WMI EVENT ALERT to configure the action or alarm after the mirror state is modified.3. Use System Monitor to view key performa