index of access log

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

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

062 Creating an indexIndexing is especially important for queries that are the primary application. A lot of times the performance problem is simply because we forgot to add an index, or we didn't add a more efficient index. If you do not index,

Index type1. Unique index: Unique index does not allow two rows to have the same index value2. Primary KEY index: Defining a primary key for a table will automatically create a primary key index, which is a special type of unique index. The primary

As a free and efficient database, MySQL is basically the first choice. Good security connection, with query resolution, SQL statement optimization, use of Read and write locks (refinement to line), things isolation and multiple version concurrency

Preface This is a study note.The learning material comes from a log blog post from Jay Kreps.The original text is very long, but I persisted to read, the harvest is very much, also deeply to Jay's technical ability, the architecture ability and to

Correct use of MySQL index Query Index is the most important tool for improving the query speed. Of course there are other technologies available for use, but in general, the biggest performance difference is the correct use of indexes. In the MySQL

Preface This is a study note.The learning material comes from a log blog post from Jay Kreps.The original text is very long, but I persisted to read, the harvest is very much, also deeply to Jay's technical ability, the architecture ability and to

In this article, we learned about the implementation principle of the index under different engines of MySQL, and in this paper we will continue to explore the use and optimization of indexes.Creating an index can greatly improve the performance of

1.oracle OptimizerThe goal of optimization is divided into 4 categories:Choose (optional)Rule (rules-based)First rows (line one)All rows (all rows)Description: Describe the execution plan for SQLObject owner: Objects SchemaObject Name: Objects