postgresql optimization

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

PHP connection and operation of PostgreSQL database method, PostgreSQL database This article describes the PHP connection and operation of the PostgreSQL database method. Share to everyone for your reference. The implementation method is as follows: Copy the Code code as follows:$PG = @pg_connect ("Host=localhost user=postgres password=sa Dbname=employes")Or Die

--Configs requiring PostgreSQL restartselect name, setting, context from pg_settings where context = ' postmaster ';postgres=# select name, setting, contextpostgres-# from pg_settings where context = ' postmaster ';name | setting | Context-------------------------------------+-----------------------------------------------+------------Allow_system_table_mods | Off | PostmasterArchive_mode | Off | PostmasterAutovacuum_freeze_max_age | 200000000 | Post

Tags: current cannot grammar GRE AST extension images Development framework COMRecently prepared for PostgreSQL database development related knowledge, this article summarizes the PPT content through the blog record sharing, this essay's main content is to introduce the PostgreSQL database basic information, and how to use the PostgreSQL database in our developme

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

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

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

SQL General optimization scheme:1. Using parameterized queries: Prevent SQL injection and precompile SQL commands for increased efficiency2. Remove unnecessary queries and search fields: In fact, in the actual application of the project, many of the query conditions are optional, can be avoided from the source of redundant functions as far as possible, this is the most simple and rough solution.3. Select the most efficient table name order: The databa

? This is to start from three aspects, one is that I have learned and used MySQL, I feel MySQL easy to get started, proficient in difficulties, the general programmer is not trained to control MySQL, there is a project, the development phase seemingly and SQL Server is not very different, But after the system is deployed to the production environment, the performance problem will be exposed soon, so I have to gig, learn to use, reconstruct the entire data access layer, (some students may ask,

1. Download To the website to download the latest PostgreSQL Studio, I downloaded pgstudio_1.2-bin. zip because there are no Tomcat in my computer. If the computer has a good configuration of tomcat, you can download Pgstudio_1.2.zip, after decompression is a war package. Download Address: http://www.postgresqlstudio.org/download/ 2. Decompression Unzip the compressed file to see the following directory: 3. Run Run in Bin directory: ./catal

fieldSELECTC.relname,Col_description (A.attrelid, A.attnum) as COMMENT,Format_type (A.atttypid, A.atttypmod) as type,A.attname as NAME,A.attnotnull as NotnullFromAty_class as C,Aty_attribute as aWHERE A.attrelid = c.oidand A.attnum > 0and a.attname = ' N_AJBS 'View table StructureSELECTAttname,typname,adsrcFromAty_attributeINNER JOIN aty_class on aty_attribute.attrelid = aty_class.oidINNER JOIN aty_type on aty_attribute.atttypid = aty_type.oidLeft OUTER joins aty_attrdef on aty_attrdef.adrelid

serialization (similar to repeatable Read-only see results submitted before the transaction starts). Set the isolation level at the transaction level using the SET TRANSACTION statement. Use set session to set at the session level. MySQL's disadvantage relative to PostgreSQL: Mysql PostgreSQL The most important engine InnoDB is very early in the control of O

Tags: blog http os using IO file AR data artTransferred from: http://blog.csdn.net/qpengyanting123/article/details/7497556(1) User utility program:Createdb Create a new PostgreSQL database (and the SQL statement: Create DATABASE is the same)CreateUser Create a new PostgreSQL user (and SQL statement: Create user is the same)DROPDB Deleting a databaseDropuser Deleting a userPg_dump to export the

How to disable the deadlock process in PostgreSQL, postgresql Process The PostgreSQL database used has no information. Google had to proceed. Finally, a solution was found in an English forum. As follows: 1. Retrieve the ID of the deadlock Process Copy codeThe Code is as follows:SELECT * FROM pg_stat_activity WHERE datname = 'deadlock database id ';In the re