create or replace index

ReprintedBytes IndexYou can use indexes to quickly access specific information in database tables. An index is a structure that sorts the values of one or more columns in a database table (for example, the last name (lname) column of the employee

MySQL index details, MySQL index detailsI. Introduction to index basics 1.1 In MySQL, indexes are also called keys. They are a data structure that the storage engine uses to quickly find records. Indexes are critical to good performance. Especially

This article is transferred from: Http://www.cnblogs.com/abcdwxc/archive/2007/12/11/990274.html ----------------------- Creates an index for a given table or view.Only the owner of a table or view can create an index for the table. The owner of a

SYS. dm_exec_requests is a powerful tool to check the performance bottleneck of SQL Server. Update statistics t_goods with fullscan --- Update table statisticsThe index leaves of clustered indexes are the data itself.The leaf node of the

With regard to the benefits of MySQL indexing, if the correct and reasonable design and use of the index MySQL is a Lamborghini, then there is no design and use of the index MySQL is a human tricycle. For tables with no indexes, a single table query

8.2.1 creates an index with the CREATE INDEX command CREATE index either creates a clustered index that alters the physical order of the table or creates a nonclustered index that improves query performance. The syntax is as follows: CREATE

With regard to the benefits of MySQL indexing, if the correct design and use of the indexed MySQL is a Lamborghini, then no design and use of the index of MySQL is a human tricycle. For tables that do not have an index, a single-table query might be

Article attribution: http://feiyan.info/16.html, I want to write to myself, but found this June summed up very detailed. Moved right over here.With regard to the benefits of MySQL indexing, if the correct design and use of the indexed MySQL is a

Article attribution: http://feiyan.info/16.html, I want to write to myself, but found this June summed up very detailed. Moved right over here.With regard to the benefits of MySQL indexing, if the correct design and use of the indexed MySQL is a

Unique indexIf the primary key is not set to a clustered index when it is created, it must be a unique nonclustered index. In fact, the unique index, the name Incredibles, is that it requires the value on that column to be unique. A unique index