sql server maintenance plan wizard

100336 lines, we remember this number Another feature of statistics is that statistics are automatically created on query columns (non-indexed columns), as followsDuring query execution, a statistic named: _wa_sys_00000003_24e8431a is created automatically.This statistic is the statistic for the COL3 column, and you can find the number of rows that are greater than or equal to 2012-10-20. In SQL Server

When using the DTS Wizard for SQL Server 2012 (Import and export data/imports exported data), the following issues occur:No problem when the source data is used directly from the tableHowever, if the source data is a query, the fields will be mapped to (varchar) and 202 (nvarchar)It is said that Microsoft has solved the bug:https://connect.microsoft.com/sqlserver

Three Join strategies in the execution planThere are three join strategies for SQL Server: Hash join,merge join,nested Loop join.hash Join: Used to handle data that is not ordered/not indexed, it creates a hash table in memory of the data (the associated key) on both sides of the Join. For example, with the following query statement, the associated two tables are not indexed, and the execution

Summary of index, foreign key, and field syntax maintenance for mysql, SQL Server, and oracle databases, and SQL Server oracle Summary of index, foreign key, and field syntax maintenance for mysql,

Parameter sniff is encountered in parameterized SQL writing in SQL Server, which leads to the rapid solution of unreasonable execution plan reuse. parametersniff Parameter sniff is an execution plan generated by reusing other parameters. As a result, the current parameter us

server, the time it takes to cache the execution plan, and the parameters of the current cached execution plan compile time.After the query to the execution plan of the corresponding stored procedure cache, it is found that the execution plan is quite different from the exe

can also be used to a certain extent to reuse the cached execution plan, which reduces (but inevitably) the number of recompilation At the same time, this approach can also take advantage of the additional benefits of parameterization, such as SQL injection, compared to an ad hoc query that is executed with a SQL string. Summarize: There are many ways to solve

Label:Original: SQL Server execution Plan cacheTags: SQL server/mssql server/database/dba/memory Pool/Buffers OverviewUnderstanding the execution plan is important for database performa

This article turns from http://543925535.blog.51cto.com/639838/1427529In the daily SQL maintenance, there are many tasks that need to be repeated periodically, we are not likely to do manual operations, such as backup jobs, rebuild maintenance index, database collation and so on.Take backup as an example, we usually put the time period of database backup at night

Read Catalogue Begin How SQL Server looks for records SQL Server Join method More specific execution procedures Index statistics: The choice of the query plan is based on Optimizing View Queries Recommended Reading-MSDN Articles For

Read SQL Server query planRead Catalogue Begin How SQL Server looks for records SQL Server Join method More specific execution procedures Index statistics: The choice of the query

Tags: Record level comprehensive access to data information TPS purpose life data First explain a concept, what the statistics are:It is simply a description of the distribution of some field data, so that SQL Server probably knows the expected size of the data to guide a database object that generates a reasonable execution plan Update policy for statistics by d

Brief introduction The nature of the SQL statement we write is simply the logic to get the data, not the physical path to get the data. When we write SQL statements to SQL Server, Query Analyzer parses statements sequentially (Parse), bindings (BIND), Query optimizations (optimization, sometimes referred to as simplif

Introduction The SQL statements we usually write are essentially the logic for obtaining data, rather than the physical path for obtaining data. When the SQL statements we write are passed to the SQL Server, the query analyzer parses, binds, and optimizes the statements in sequence), Execution (Execution ). In addition

To analyze the performance of a query, you can view {Tagshow (event, '% D6 % B4 % D0 % D0 % BC % C6 % BB % AE ');} "Href =" javascript:; "target =" _ Self ">Execution Plan. Execution Plan description {Tagshow (event, 'SQL ');} "Href =" javascript:; "target =" _ Self ">SQL{Tagshow (event, '

SQL Server Performance Tuning 3 (Index) MaintenanceHeat1 reviews Brook Stream GrassSQL Server Performance Tuning 3 (Index) MaintenanceObjectiveThe previous article describes how to improve the query performance of a database by building an index, which is really just the beginning. Subsequent to the lack of proper maintenanc