postgresql query optimization

Tags: MySQL database If a large table contains millions, tens of millions, or even hundreds of millions of data records, the query results should be queried in real time within 10 seconds. What should I do? How to optimize it? In my current project, there is a table with more than 10 million rows of data and more than 3 GB of data. Now we need to perform query statistics on the data in the table. Previo

Directory I. Optimization Overview Ii. query and index optimization Analysis 1. performance bottleneck locating Show command Slow query log Explain analysis Query Profiling Analysis Query 2 Index and

MySQL paging query optimization solution for millions of data and mysql paging Solution When there are tens of thousands of records in the table to be queried from the database, all the results of one-time query will become very slow, especially with the increase of data volume, you need to use paging query. There are

Query optimization Technology of databaseQuery optimization Technology of databaseDatabase system is the core of MIS, and online transaction processing (OLTP) and online analytical Processing (OLAP) based on database is one of the most important computer applications in banks, enterprises and government departments. From the application examples of most systems,

MySQL Query statement optimizationIndex optimization, query optimization, query caching, Server Setup optimization, operating system and hardware optimization, application-level

The following articles mainly describe five useful methods for MySQL query optimization. Anyone familiar with SQL statements knows that if you want to operate a task, SQL statements can be written in many ways, but the query performance varies with different writing methods. This article lists five MySQL query

Five practical tips for MySQL Query Optimization, This article summarizes and analyzes the MySQL query optimization techniques. We will share this with you for your reference. The details are as follows: Anyone familiar with SQL statements knows that if you want to perform operations on a task, SQL statements can be wr

Database-query optimization of the relational database systemQuery Optimization It plays an important role in the relational database system.Relational query optimization is a key factor affecting RDBMS performance.Due to the high semantic level of relational expressions, th

Many programmers think that query optimization is the task of the DBMS (Database Tutorial management System), which is not related to the SQL statements written by programmers, which is wrong. A good query plan can often improve the performance of the program by dozens of times times. A query plan is a collection of SQ

;//retrieving the first 5 records lines MySQL's limit brings great convenience to paging, but when the amount of data is large, limit performance drops sharply. also take 10 data, the following two sentences are not a number of levels. 10000,0,ten Instead of using limit directly, you first get the ID of offset and then use the limit size directly to get the data. According to his data, it is significantly better to use limit directly.Here I use the data in two different situations

member table and one distributed partitioned view on each server. The location of the data is transparent to the application.11. Rebuild the index DBCC REINDEX, DBCC INDEXDEFRAG, shrink data and log DBCC SHRINKDB,DBCC shrinkfile. Sets the auto-shrink log. For large databases do not set the database autogrow, it will degrade the performance of the server. There's a lot of emphasis on T-SQL, and here's a list of common points: first, the DBMS processes the qu