PostgreSQL

Objective There are requirements in the project to vertical table, that is, according to the time interval to split the data into N tables, PostgreSQL provides the function of the partition table. A partitioned table actually divides a large

PostgreSQL is a role to manage database access, we can see a role as a database user, or a group of database users. A role can have database objects, such as tables, indexes, or other roles on those objects to control which users have permissions on

Background For financial-level scenarios, 2 replicas are usually not enough, and users may need multiple replicas. For example, a master 4 from, requires in addition to the master, also requires 2 synchronized copies, others can be asynchronous

PostgreSQL Create a databaseTo create a Xifenfei library using the shell-level createdb command-bash-3.2$ Createdb XifenfeiSystem Authentication Login PostgreSQL DatabaseUsing the Xifenfei database in the psql login PostgreSQL-bash-3.2$ Psql

In this article, we use the MySQL 4.0.2-alpha and PostgreSQL 7.2 to compare, because MySQL 4.0.2-alpha started to support the concept of transactions, so this comparison for MySQL should be more advantageous. We don't want to be just a performance

After figuring out the principle of the log number, a little bit of forgetting about it for a while, simply tidying it up again:(i) Wal file naming rules1) Xlog log file (10.1 becomes Pg_wal) in the Pg_xlog directory below the $pgdata

PostgreSQL automatically backs up and deletes Windows scripts for backup files 10 days ago.The first step, create the script, name the Back.bat file@ECHO off@setlocal ENABLEEXTENSIONS@CD/d"%~dp0" Setpgpassword=PasswordSET Pgpath=

Example:select * from test limit 2 offset 2;Limit: How many data are checkedOffset: Starting from the subscript, the subscript starts at 0 and cannot be a negative number.Offset Calculation formula:var offset=(pageIndex-1) * pageSize //

It is faster to make a link query to a table in a database than to use in, how do I avoid using in?PostgreSQL provides the function of regexp_split_to_table, which we can use to avoid problems with inHow to use:Table A , table a has field IdUsing in

The server doesn ' t grant access to the Database:the server reportsFatal:no pg_hba.conf entry for host ' 192.168.0.123 ', user ' postgres ', database ' Postgres ' fatal:no pg_hba.conf entry for Host "192.168.0.123", User "Postgres", Database

The installation process is simply carried over:1. Before looking at the code, we need to load npgsql and Petapoco into the current project, and I will use NuGet to add to the current project as follows:Install-package NpgsqlInstall-package Petapoco2

Since MySQL was acquired by Oracle, PostgreSQL has become the first choice for open-source relational databases.This article describes the installation and basic usage of PostgreSQL for first-time users to get started. The following is based on the

1. BackgroundBefore the end of the day, the database has a temporary table cert_display_tmp used to do the interface display, the table data is from T_cert_sample, Ying said the data is incorrect, and then manually perform the update function,

Mybatis+postgresql PlatformRecently there is a database of projects using PostgreSQL, using the original ecological mybatis operation data, the original ecological Nothing bad, But there is a tk.mybatis tool in the country to help us do a lot of

Org.postgresql.util.PSQLException: Field index exceeds license range: 3, Number of columns: 2.Today, after writing the SQL query, the background has been error display the above information. Looking at the error for no reason at all, we re-examined

Installation process: 1. Configuration--prefix=prefix Install all files under the directory PREFIX instead of Usr/local/psql--with-pgport=number Set number as the default port number for server and clients,the default is

SOURCE side to open the target of the relevant access rights target: 1. Create a view of the remote table create view V_bill_tbl_version_update_control_info as SELECT * from Dblink (' hostaddr= 10.10.10.8 port=4321 dbname=postgres user=postgres

theBucardoProject have released itsNagios Plugins for PostgreSQLAnd we can extract from them this nice view on order to check for table and indexbloat into ourPostgreSQLdatabases:Here is a script to check the usage of the tablespace:CREATE OR

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

In SQL, query conditions need to be divided into three types in the query optimization stage. The three types of conditions have different effects and can be converted to each other in some cases.First, describe the SQL statement execution steps,