postgresql tuning

Xin Xing sorts out some common non-SQL operations in postgresql. Xin Xing postgresql The operations mentioned here are performed after we use psql to enter the postgresql client. They are not SQL statements, but they are usually important. Below are some common sorting operations: (1) list all databases. Use the \ l command or the \ list Command. Note that the

Create a postgresql Partition Table. Create a postgresql partition table. In postgresql, there is no partition table creation command. It is created by creating rules such as inherited tables and constraints. The steps are cumbersome and troublesome, and a method is encapsulated. To create a partition table: CREATE TABLE "odl"."user_action_fatt0" ("date_id" nume

Tutorial on implementing recursive query in PostgreSQL, postgresql Recursion Introduction I am working on a program in nilint32 (Open Source !) It is used to design and initiate surveys. The following is an example of a survey: Internally, it indicates the drop: A Survey involves many questions (question ). A series of problems can be classified into (optional) one category. Our actual data structure will

Commonly used time and date scripts in PostgreSQL tutorial, postgresql tutorial Obtain System Time Functions select now(); --2013-11-28 16:20:25.259715+08select current_timestamp; --2013-11-28 16:20:38.815466+08select current_date; --2013-11-28select current_time; --16:21:08.981171+08 Time Calculation-- Use interval Select now () + interval '2 Day'; -- 16:21:47. 610118 + 08 2 days later sele

1. DownloadGo to the official website to download the latest PostgreSQL Studio, I downloaded Pgstudio_1.2-bin zip, because there is no Tomcat on my computer.Suppose you have a computer with Tomcat configured to download Pgstudio_1.2.zip and then a war package after decompression.: http://www.postgresqlstudio.org/download/2. UnzipUnzip the compressed file to see, for example, the following folder:3. ImplementationExecute under the Bin folder to start T

GIS image cutting performance tuning and GIS image Performance TuningStatus Quo and objectives DellR920 Server, virtualized vmware vsphere 5.5 system, Guest System Windows Server 2012 R2. Deploy software ARCGIS 10. Image graph cutting test: the original cut takes 70 hours, And now it takes 17 hours. There is still room for further optimization. Debugging objectives: 1. Verify the optimal graph cutting parameter configuration in the virtualization env

timeout; b read timeout; c write timeout);2.2. Parallelization of the serial request;A) use of curl_multi_* ();b) Use the swoole extension. 3. compress the PHP interface output:Using gzip compressionBenefits: Facilitates faster reception of data by client side;Cons: Extra CPU overhead 4. Cache Duplicate content: multiple requests, the content is not changed under the circumstances; 5.smarty Tuning and time window overlap ideas (which can be used in c

Performance optimization is to improve the system performance, reduce energy usage, or reduce the impact of applications on other parts. If the optimization is hasty or there is no measurement, of course, performance optimization may have a bad effect. Performance optimization is to improve the system performance, reduce energy usage, or reduce the impact of applications on other parts. If the optimization is hasty or there is no measurement, of course, performance optimization may have a bad e

An example is provided to briefly introduce arrays in PostgreSQL and postgresql. PostgreSQL has many out-of-the-box data types, from standard digital data types, to geometric types, and even network data types. Although many people ignore these data types, they are one of my favorite features. The array data type, as you expected, can be used to store array data

Basic PostgreSQL commands and PostgreSQL commands 1. Change the table name Alter table name rename to new table name 2. Change the field name Alter table name rename field name to new field name 3. Change the field type. For example, the original type of the ID field is character varying (50) and the new type is integer. Where, the ID contains numbers such as 1, 2, and 3. Use the following statement to cha

A basic knowledge1.1 What is performanceBefore performance tuning, let's start by understanding what performance is. With regard to performance, I think everyone who has studied Java can list a few points and even talk about it. In the Java TM Platform performance, the following five aspects are defined as criteria for judging performance:1) The performance of the operation--which algorithm performs the best performance?2) Memory allocation-How much m

tuning needs to focus on several aspects of memory tuning CPU using tuning lock competitive tuning I/O Tuning Fundamentals: The number of objects to be transferred to the old age is minimized. Reduce the execution time of full GC. The goal is to minor GC time within 100MS an

Comparison of Oracle, mysql, sqlserver, and postgresql statements, postgresql and oracle 1. Paging Oracle:SELECT * FROM (select a. *, rownum rn from (select T. * from sj_receiptinfo t WHERE t. taxno like concat ('%', CONCAT (?, '%') Order by t. id desc) a where rownum Mysql:Select * from tableName where ConditionLimit (Current page number * Page capacity-1),Page size pagesize SqlServer: SELECT w2.n, w1.

PostgreSQL tutorial (16): System View Details, postgresql View I. pg_tables: This view provides access to useful information about each table in the database. Name Type Reference Description Schemaname Name Pg_namespace.nspname The schema name of the table. Tablename Name Pg_class.relname Table name. Tableowner Name

Five tips for Instagram to improve PostgreSQL performance, postgresql Performance Optimization As Instagram grows, Postgres continues to serve as a solid foundation for Instagram and stores a vast majority of user data. Less than a year ago, we also wrote on our blog that Instagram "stores a large amount of data" and adds 90 pieces of data per second. Now, this data has increased to 10000 pieces of peak dat

PostgreSQL recursive query for tree structure query and postgresql Recursion A very interesting feature found during Postgresql's use is that recursive queries can be used for results that require a tree-like structure. For example, the data structure of common company departments is similar to the following SQL statement when we design the table structure. If parent_id is NULL, it indicates the top-level

PostgreSQL date calculation functions, postgresql Functions I. connector in each data SqlServer connector: + (plus sign) Sqlite connector:. (point) PostgreSQL connector: | (OR) II: Today, when I was computing data in PostgreSQL, I had to record a few materials ~! Functions and variables used To_char (), Date (), now ()

Enable postgresql remote permissions and enable postgresql Preface: Previously, only the remote permission of the specified IP address of postgresql will be configured. Later, a client wants to remotely connect to postgre and view data, but her IP address changes frequently, as a result, I had to re-set the settings every time, and finally found the method. Now

Label:In the process of reading any questions, welcome to communicate togetherEmail:[email protected]qq:1494713801One, PostgreSQL time type conversion--The time type is converted into character type select To_char (current_date, ' yyyy/mm/dd '); select To_char (current_date, ' yyyy-mm-dd '); select To_char (now (), ' yyyy-mm-dd '); select To_char (Current_timestamp, ' HH:MI:SS '); select To_char (Current_timestamp, ' yyyy/ Mm/dd HH:MI:SS '); --The str

Label:Objective:Recently do data synchronization, need to get data from PostgreSQL, found that once the data is more, then the speed of reading is very slow, and memory consumption is very much GC not fall.Code Sample:In order to facilitate the explanation, the following writing the case code, from B2c_order to obtain data, this data table about 6G. Package Com.synchro; Import java.sql.*; /** * Created by Qiu.li on 2015/10/16. * /public class Test