ltrim rtrim performance in sql server

databases after a large number of updates. The system databases that must be backed up includemsdb、MasterAndModel。 If you have any databases that use replication on the server instance, you must also back upDistributionSystem database. By backing up these system databases, you can restore and restore the SQL Server system in the event of a system failure, such a

There are four variables that affect the performance of tape backup devices and allow SQL Server backup and restore performance operations to increase the linear proportions of the system by substantially adding more tape devices. Software data block size Number of tape devices sharing a small computer system interfa

parameterization.Sqlserver:sqlstatistics/failed auto-params/secNumber of failed automatic parameterization attempts per second. the value should be very small. Note that in later versions of SQL Server, automatic parameterization is also known as simple parameterization.Sqlserver:sqlStatistics/batch requests/secNumber of Transact- SQL command batches received pe

If you suspect that computer hardware is the main cause of affecting the Performance of SQL Server, You can Monitor the load of the corresponding hardware through SQL Server Performance Monitor to confirm your guesses and identify

(user_lookups), if these two values are small, you might consider dropping the index.When you restart the SQL Server service, the various counters in the Sys.dm_db_index_usage_stats system view are initialized to null values. In addition, whenever data is detached or closed (for example, because Auto_Close is set to ON), all data rows associated with the database are deleted. When an index is first used, i

to archive, partition, table sharding, etc) Software System (operating system optimization, database system configuration, resource planning and monitoring, etc) Hardware infrastructure (Device specifications, hardware performance, Server Load balancer, Disaster Tolerance, etc) SQL statement writing, indexing and statistics, transactions and locks, application a

In the last 3 articles, we discussed a list of different queries that reflect the current state of the server. Initial SQL Server performance issues (1/4): Server overview Initial SQL

can specify whether the event can be "lost". This means that if there is not enough memory to buffer an event, it can be discarded directly. The default setting is to allow a single event to be discarded, but you can also allow the entire event buffer to be lost (for sessions where the event buffer is quickly filled up), or even to specify that no events should be lost.You should take extra care when using the last option, because it forces the code that fires the event to wait until there is e

fragmentation has occurred? Execute the following SQL statements in your database. (Sql2005 or earlier database, replace the database name "adventureworks") Select object_name (DT. object_id) tablename, Si. nameindexname, DT. avg_fragmentation_in_percent asexternalfragmentation, DT. avg_page_space_used_in_percent asinternalfragmentationfrom (select object_id, index_id, avg_fragmentation_in_percent, avg_page_space_used_in_percent from sys. dm_db_index

Tags: max des from work query optimization select Run ASE Query1. Import trace files, such as duration >5000ms, collected by SQL Server profile into the sample table analysis or with the query optimizer advisor 2. You can use the DMV dynamic management view to query analysis SQL Server

Transferred from: http://www.cnblogs.com/MR_ke/archive/2010/08/25/1807856.htmlSQL 2005 Performance TuningSQL Server runs for a period of time, and as data accumulates, SQL runs less efficiently, and in order to use business system normal actions, IT departments often need to spend a high price on SQL tuning experts to

affected)(One row is affected)SQL Server execution time:CPU time = 0 ms, occupied time = 528 Ms.(Row 3 is affected)Table 'worktable '. Scan count 0, logical read 0, physical read 0, pre-read 0, lob logical read 0, lob physical read 0, lob pre-read 0.Table 'tb2 '. Scan count 3, logical reads 1002, physical reads 0, pre-reads 0, lob logic reads 0, lob physical reads 0, and lob pre-reads 0.Table 'tab1 '. 1 sc

uses the pubs database. SELECT au_id, au_lname, au_fname from authors WHERE au_lname = ' White ' the index established on the following columns will be useful for the optimizer au_lname au_lname, au_fname The indexes built on the following columns will not work well for the optimizer Au_address au_fname, au_lname consider using narrow indexes on one or two columns, narrow indexes are more efficient than multiple indexes and composite indexes. With a narrow index, there will be more rows a