PostgreSQL

One of the big selling points of the Postgre database is the way it handles concurrency. Our expectations are simple: reading never blocks writing, and vice versa. Postgres this through a mechanism called multiple versioning concurrency control

Background Car shift is smooth, usually depending on the number of stalls, or shifting technology. The more the number of stalls, shifting feeling will be about smooth, less number of stalls, the shift may have more obvious duncuo feeling.

MySQL has a and excellent syntax create TABLE ... like, you can quickly copy a table and create a copy of it. PostgreSQL has a similar syntax and is more flexible, but pay attention to the details.Let's look at MySQL syntax: CREATE TABLE ... likeThe

Recently learning hibernate, the common tutorial is to go with MySQL, because the company's local computer with PG, so try to do a PG small demo. He is also learning to write, only to deepen the impression. Words do not say much, direct start;A)

Multiple SELECT statements can be set using Union,intersect and except, where union is used to find unions, intersect for intersection, and except for differential sets. Use the followingQuery1 UNION Query2Query1 INTERSECT Query2Query1 EXCEPT

The Navicat for PostgreSQL database uses users and groups to manage database access permissions, and users have database objects, such as databases, on which you can specify permissions to other users, and control the scope and permissions of other

Main Library ConfigurationPg_hba.confHost replication All 10.2.0.0/0 TrustPostgresql.conflisten_addresses = ' * ' max_wal_senders = 5wal_level = Hot_standbyRestarting the main libraryConfigure from LibraryInstallationInstall with Yum (source

1.excel file ProcessingDelete header row, save as comma delimiter csv file2. file format processing Notepad + +1). convert Files to UNIX format2). format conversion to UTF8 no BOM3. Uploading to the database importPrecautions:1). Character set

PostgreSQL type ConversionLike Oracle, PostgreSQL also has a powerful type conversion function, with just two types of conversion examples below.--1 Examplepostgres=# Select 1/4;? column?----------0(1 row)In PG If you want to divide and want to keep

MySQL cannot support the data version from the most basic data engine to the process structure. Causes its function to block "concurrency", does not support the most basic transaction, InnoDB does not reach the basic transaction requirements, any

PostgreSQL server run on Linux, client installed on Windows or Linux, using Navicat connection, need to modify the server configurationConfiguration method:1. Modify the server-side/etc/postgresql/9.3/main/postgresql.conf file to#listen_address = '

Recently saw the topic of PostgreSQL more, search for it and MySQL comparisonCicadaLinks: http://www.zhihu.com/question/20010554/answer/74037965Source: KnowThe advantages of PG relative to MySQL:1, the standard implementation of SQL is better than

Developers who have just been familiar with PG will encounter some problems when they touch pg.The common performance is to bump into some slow SQL. Don't throw up the groove at this time. The vast majority is not a problem, a slight grammatical

Original address: http://blog.chinaunix.net/uid-20684384-id-1895247.html1. Setting the remote access authentication mechanismEdit $POSTGRES/data/pg_hba.conf file,# TYPE DATABASE USER cidr-ADDRESS method# IPv4 local

The system tables show the information under the current operations database, and the objects are from the current database. Because different system tables use different name fields to record the OID of different objects, the table references that

I. Deployment notes1.1 Implementation EnvironmentThe experimental environment for this document is as follows:Pgsql Host: 192.168.1.45Pgsql Standby Machine: 192.168.1.50Software and system versionsPgsql version: Pgsql 9.2.4Linux version: Redhat 5.81.

PostgreSQL two types of transaction isolation levels:Read Committed: The default isolation level in PostgreSQL. When a transaction runs at this isolation level, a select query can see only the data that was committed before the query was started and

Q:I have been trying to make we database clients pro-active about not filling up the partition on which the database they a Re using resides.As all of our clients is on the same host as the database manager, it should is easy enough for user-created

Setting up PostgreSQL master server under Ubuntu (Method 1)Install slightlyPostgreSQL master server:$ vi/etc/postgresql/9.1/main/postgresql.confPress A or I to enter edit modelisten_addresses = ' * ' (default is commented, this does not change when

First, the environmentubuntu14.04postgresql-9.4.3Second, installation1. Dependent Package Installationsudo Install libperl-dev python-dev libreadline-gplv2-dev Zlib1g-dev2. Download PostgreSQL, compile and installWGer https://ftp.postgresql.org/pub/