PostgreSQL

5.ModifyTable nodeLet's look at an example of a modifytable node:postgres=# explain update test_01 set id = 5 where name = 'xxx'; QUERY PLAN--------------------------------------------------------------- Update on test_01

Create a databaseCREATE DATABASE Test with OWNER = postgres ENCODING = ' UTF8 ';Enter the console method to execute the command under the installation purpose bin of PostgreSQL: Psql database name,Example:/usr/local/pgsql/bin/psql mydbSpecify host,

PostgreSQL is an object-relational database management system (ORDBMS) based on the POSTGRES, Version 4.2, developed by the University of California, Berkeley computer department. Many of POSTGRES's leading concepts only appear in the business

Turn off SELinuxGetenforceSetenfroce 0Vi/etc/selinux/configSelinux=disabledselinuxtype=targetedShutting down the firewall#chkconfig iptables off#service iptables StopInstalling Pgsql# rpm--FORCE-IVH openssl-1.0.1e-42.el6.x86_64.rpm postgresql94-libs-

PostgreSQL supports case,coalesce,nullif,greatest,least conditional expressions, and using them can sometimes simplify many feature implementations.Test tableTest=#Create TableTbl_test (IDint, namevarchar( +), Sexvarchar(1));CREATE TABLETest=#Insert

General:\copyright display the use and release license terms for PostgreSQL\g [file] or; Execute the query (and write the results to a file or | pipeline)\h [name] SQL command syntax description, with * Show all commands syntax description\q Exit

A table in a relational database is very similar to a table on paper: It consists of rows and columns. The number and order of fields are fixed, and each field has a name. The number of rows is variable (it reflects the amount of data stored at a

PostgreSQL is a relational database management system (RDBMS). This means that it is a system for managing data that is stored in relational form. A relationship is actually a mathematical salutation to a table . Today, the concept of storing data

PostgreSQL Update and delete property from Jsonb column Up vote 2 down vote favorite From this article, I tried to update or delete property of a JSONB column:CREATE TABLE xxx (id BIGSERIAL, data JSONB);INSERT INTO xxx(data) VALUES(

A password file contains the five fields we need to connect, so we can use file permissions to make the password more secure.Host:port:dbname:user:passwordsuch as Myhost:5432:postgres:sriggs:moresecureThe password file is set using an environment

PostgreSQL Source Installation:Download source v9.4.5 compile installation from http://www.postgresql.org/download/./configureMakeSuMake install//install completeAddUser PostgresMkdir/usr/local/pgsql/dataChown

In PostgreSQL, the conversion between binary, decimal, and hexadecimal is very convenient, as follows:Decimal turn 16 binary and binarymydb=# SELECT To_hex (10);To_hex--------A(1 row)mydb=# SELECT 10::bit (4);Bit------1010(1 row)hexadecimal to

Some of the functions currently in PostgreSQL are also present in hive, so this is illustrated today with PostgreSQL as an example, which can be applied to hive as well. 1. Create a table CREATE TABLE Employee (empid int, DeptID int, salary DECIMAL (

First, the sceneThere may be a problem with the configuration when installing PostgreSQL "The problem is that I changed the pg_hba.conf in the local column ident to peer will be wrong" cause the service does not come, error is as follows:[[Email

1. Pre-maintenancepostgres=# \d+ test                                                           table "Public.test"   Column |             Type              |                      Modifiers| Storage | Stats target |  Description--------+-------------

1. Create a database:1) Login Bin directory, createdb.exe-u Postgres-e mydb;-U indicates the login user name of this operation, if not write will take Windows login account, such as Administrator, will prompt no creation permission;2. Log in to the

1. Original address: http://my.oschina.net/slhong/blog/96159Basic description before configuration: Win7 +python2.7.3+postgresql9.22+ Django1.4.3 Psycopg2-2.4.6.win32-py2.7-pg9.2.2-release Steps to use: Install Python

Create or Replace function decode (p_condition boolean, p_fist_val text, p_last_val text) returns text as$ $declare V_ret_val Text;begin/* Function Description: Analog ternary expression (condition-value1:value2); * Parameter Description:

Today is depressing. In the SHP file of National Basic Geographic Data, the provincial data adcodd99 is int type. I imported it into PostgreSQL and it became int4 type. However, the adcodd99 of the district-level data is portable and imported

Processing of null values in PostgreSQL When a field value is null in the addition, subtraction, multiplication, division, and Division operations, the output results often disappoint us and we cannot get the expected values, you can use coalesce to