An Introduction to Postgresql

‫خدا‬ ‫نام‬ ‫به‬
‫اطلاعاتی‬ ‫بانک‬ ‫با‬ ‫آشنایی‬ ‫سمینار‬
PostgreSQL
‫اول‬ ‫بخش‬
‫پاییز‬۱۳۹۴

‫مقدمه‬
●
‫بازیابی‬ ‫و‬ ‫ذخیره‬ ‫توانایی‬ ‫بر‬ ‫اعلوه‬ ،‫باز‬ ‫متن‬ ‫اطلاعاتی‬ ‫بانک‬ ‫هترین‬‌‫ت‬ ‫پیشرفت‬ ‫پستگرس‬
.‫یباشد‬‌‫ت‬ ‫م‬ ‫هاها‬‌‫ت‬ ‫داد‬ ‫پردازش‬ ‫برای‬ ‫کاری‬ ‫چارچوب‬ ‫یک‬ ‫اطلاعات‬
●
‫هسازی‬‌‫ت‬ ‫پیاد‬SQL2011
●
)‫پذیری‬ ‫توسعه‬ ‫قابلیت‬،‫اها‬ ‫افزونه‬pgxn(
●
‫یی‬ ‫گرا‬ ‫شی‬
●
‫تاهای‬‌‫ت‬ ‫قابلی‬NoSql
●
: ‫بزرگ‬ ‫سازمان‬ ‫یک‬ ‫در‬ ‫استفاده‬ ‫جهت‬ ‫مناسب‬ ‫امکاناتی‬ ‫دارابودن‬
–‫قالب‬ ‫در‬ ‫اطلاعاتی‬ ‫بانک‬ ‫اشیاء‬ ‫بندی‬ ‫دسته‬schema
–‫امنیت‬ ‫و‬ ‫دسترسی‬ ‫کنترل‬
–) ‫متنوع‬ ‫داده‬ ‫انواع‬Arrays ،IPV4 ،IPV6 ،xml ،UUID ،Geometric ،Composite(
–‫نویسی‬ ‫برنامه‬ ‫زبان‬ ‫چندین‬ ‫از‬ ‫پشتیبانی‬
–، ‫فایل‬ ، ‫سرویس‬ ‫وب‬ ، ‫اطلاعاتی‬ ‫بانک‬ ) ‫مختلف‬ ‫داده‬ ‫منابع‬ ‫به‬ ‫اتصال‬hadoop(...‫و‬

‫پستگرس‬ ‫در‬ ‫نویسی‬ ‫برنامه‬ ‫ناهای‬‌‫ت‬ ‫زبا‬
● C
● PlpgSQL
● Python
● PLV8
● Ruby
● Perl
● R
● TCL
● JAVA
● ...

‫؟‬ ‫میکنند‬ ‫استفاده‬ ‫پستگرس‬ ‫از‬ ‫کسانی‬ ‫چه‬
●
: ‫اینستاگرام‬۴۰۰‫کاربر‬ ‫میلیون‬
●
Open Street Map
●
Sony Online Entertainment
●
(‫داده‬ ‫حجم‬ ‫بایت‬ ‫پتا‬ ‫)دو‬ ‫مشتریان‬ ‫رفتار‬ ‫:آنالیز‬ ‫یااهو‬
●
) : ‫اپل‬OS X Lion(
●
‫زمین‬ ‫به‬ ‫ارسال‬ ‫و‬ ‫فضا‬ ‫در‬ ‫متری‬ ‫تله‬ ‫هاهای‬‌‫ت‬ ‫داد‬ ‫آوری‬ ‫جمع‬ : ‫فضایی‬ ‫ایستگاه‬
●
) ‫ردیت‬reddit‫رنکینگ‬ ‫با‬ ‫اجتمااعی‬ ‫شبکه‬ ‫یک‬ :(۳۲‫شده‬ ‫نوشته‬ . ‫دنیا‬ ‫در‬
‫پایتون‬ ‫بزبان‬
●
Odoo‫یا‬Open ERP
●
Open bravo

‫مقدمه‬
●
‫های‬‌‫ت‬ ‫رابط‬ ‫و‬ ‫گرا‬ ‫شی‬ ‫اطلاعاتی‬ ‫بانک‬ORDBMS
–(‫اها‬ ‫نقش‬ ، ‫بری)جدول‬ ‫ارث‬
CREATE TABLE cities (name text,  population real,altitude  int);
Create type state  as
        ( state_code int, state_name varchar(2));
CREATE TABLE capitals (state state ) INHERITS (cities);
insert into capitals values ('mashhad',300,1,(1,'KH'));
select   *  from only cities;
‫داده‬ ‫نوع‬ ‫یک‬ ‫جدول‬ ‫اهر‬

‫پستگرس‬ ‫انشعابات‬
● PostgreSQL Advanced Plus : like oracle.
● Netezza : a popular database choice for data warehousing.
● Tpostgres : with tPostgres, you use the packaged pgtsql language
extension to write functions that use T-SQL
● BigSQL : is a marriage of the two elephants: PostgreSQL and Hadoop
with Hive.BigSQL comes packaged with hadoop_fdw , an FDW for querying
and updating Hadoop data sources.
● Postgres-XL : built-in Massively Parallel Processing (MPP) capability
and data sharding across servers.

Postgresql-XL
● OLTP writeintensive workloads
● Business Intelligence requiring MPP parallelism
● Operational data store
● Keyvalue store
● GIS Geospatial
● Mixedworkload environments
● Multitenant provider hosted environments

‫پستگرس‬ ‫ساختار‬
● Service : More than one service can run on a physical server as long as
they listen on different ports and don’t share data storage.
● Database : Default database is postgres.
● Schema : immediate next level of organization within each
database,Default Schema is Public,everything you create into public by
default unless you change the search_path of the database.
● Catalog : system schemas that store PostgreSQL built-in functions and
meta-data .pg_catalog , which has all the functions, tables, system views,
casts, and types packaged with PostgreSQL; and information_schema ,
which consists of ANSI standard views that expose PostgreSQL
metainformation in a format dictated by the ANSI SQL standard.

● Variable : search_path,work_mem,superuser_reserved_connections… : SHOW ALL
● Extension : per database , like add-ons,postgis , procedural
languages(plv8,python,perl)
● Table
– foreign table and foreign data wrapper: like database links ,
link to Mssql server , Oracle , Mysql , CSV , Webservice like Twitter.
● Tablespace:A tablespace is the physical location where data is stored
● View : materialized views like Oracle.
● Function : same as stored ptocedures in other database engines.
● Language : three base procedural languages :SQL,PL/pgSQL, and C,other
languages can install : Python, JavaScript, Perl, and R

● Operator
● Data type : array … , Custom DataType
● Cast : custom cast.
● Sequence : like oracle sequence,PostgresSQL automatically creates
sequences when you define a serial column.
● Row
● Trigger:In version 9.1, a data change in a view can fire a trigger. In
version 9.3, data definition language (DDL) events can fire triggers.
● Rule

Operator
CREATE OR REPLACE FUNCTION is_zero(int_in integer)
  RETURNS boolean AS
    $BODY$
    begin
       if $1 = 0  then
         return true;
       else
         return false;
       end if;
   End;
$BODY$
LANGUAGE plpgsql VOLATILE
CREATE OPERATOR !# (PROCEDURE = is_zero, LEFTARG = integer);

Operator
CREATE OR REPLACE FUNCTION plus_string(text,text)
RETURNS text AS
$BODY$
begin
return $1 || $2;
End;
$BODY$
LANGUAGE plpgsql VOLATILE;
CREATE OPERATOR + (PROCEDURE = plus_string, LEFTARG = text , RIGHTARG = text);
Select '10' + '10';

CAST
CREATE CAST (source_type AS target_type)
    WITH FUNCTION function_name (argument_type [, ...])
    [ AS ASSIGNMENT | AS IMPLICIT ]
    WITHOUT FUNCTION
    WITH INOUT

Custom CAST
create function numeric_to_boolean(numeric)
returns boolean immutable language sql as
$$
   select case
     when $1 > 0 then true
     else false end
$$
create cast (numeric as boolean)
  with function numeric_to_boolean(numeric)
as implicit

Rule
create table city_log
     ( log_time timestamp ,
       description varchar(100));
create or replace rule city_log  as
on insert  to cities
do also
insert into city_log
  values (now() , NEW.name ||  ' is inserted!' );
CREATE RULE "_RETURN" AS
    ON SELECT TO schema1.vw_t1
    DO INSTEAD
        SELECT * FROM schema2.tbl_t1;
‫ساختار‬ ‫و‬ ‫است‬ ‫ویو‬ ‫دومی‬ : ‫نکته‬
. ‫باشد‬ ‫یکی‬ ‫باید‬ ‫دو‬ ‫هر‬

‫اطلاعاتی‬ ‫بانک‬ ‫مدیریت‬
●
‫مسیر‬ ‫در‬ : ‫کانفیگ‬ ‫لهای‬‌‫ه‬ ‫فای‬
Cent OS : /var/lib/pgsql/9.3/data
Ubuntu 15.04 : /etc/postgresql/9.3/main
● Postgresql.conf : IP , Port , Memory, Log.
● pg_hba.conf : Controls security. It manages access to the server,
dictating which users can log in to which databases, which IP addresses or
groups of addresses can connect, and which authentication scheme to
expect.
● pg_ident.conf : maps an authenticated OS login to a PostgreSQL user.

: ‫کانفیگ‬ ‫فایلهای‬ ‫مسیر‬ ‫آوردن‬ ‫بدست‬
SELECT name, setting FROM pg_settings WHERE category = 'File Locations';
: ‫کانفیگ‬ ‫فایل‬ ‫در‬ ‫ها‬ ‫متغییر‬ ‫برخی‬ ‫مقدار‬ ‫آوردن‬ ‫بدست‬
SELECT name, context , unit ,setting, boot_val, reset_val
FROM pg_settings
WHERE name IN ( 'listen_addresses', 'max_connections', 'shared_buffers',
'effective_cache_size', 'work_mem', 'maintenance_work_mem')
ORDER BY context, name;
Show max_connections;
Show all;

:‫کانفیگ‬ ‫فایل‬ ‫تغییرات‬ ‫ااعمال‬ ‫نحوه‬
‫اطلاعاتی‬ ‫بانک‬ ‫سطح‬ ‫در‬
1)SELECT pg_reload_conf();
2)pg_ctl reload D your_data_directory_here
‫اعامل‬ ‫سیستم‬ ‫سطح‬ ‫در‬
3)service postgresql9.3 reload
4)Systemctl reload postgresql.service

‫اطلاعاتی‬ ‫بانک‬ ‫به‬ ‫اتصالت‬ ‫مدیریت‬
SELECT * FROM pg_stat_activity;
  Returns procid
Cancel Query :
  SELECT pg_cancel_backend(procid)
Kill the connection :
  SELECT pg_terminate_backend(procid)
Kill all user Connections :
  SELECT pg_terminate_backend(pid) FROM
  pg_stat_activity WHERE usename ='some_role';

‫شها‬‌‫ه‬ ‫نق‬Roles
Default role for database  is postgres.
CREATE ROLE leo LOGIN PASSWORD 'king' CREATEDB VALID UNTIL
'infinity';
  CREATEDB modifier grants database creation rights
CREATE ROLE regina LOGIN PASSWORD 'queen' SUPERUSER VALID
  UNTIL '202011 00:00';

‫گروهی‬ ‫شهای‬‌‫ه‬ ‫نق‬Group Roles
●
‫قابلیت‬ ‫گروهی‬ ‫شهای‬‌‫ه‬ ‫نق‬login‫از‬ ‫گروهی‬ ‫دربردارنده‬ ‫بعنوان‬ ‫و‬ ‫ندارند‬
.‫دارند‬ ‫کاربرد‬ ‫ها‬ ‫مجوز‬
CREATE ROLE students INHERIT;
any member of royalty will automatically have rights granted to the royalty role
GRANT students TO studentuser1;
GRANT students TO studentuser2;

Tablespaces
● Tablespaces logical names to physical
locations on disk.
● pg_default : stores all user data.
● pg_global : stores all system data.
● CREATE TABLESPACE secondary LOCATION '/data/meedc';
● ALTER DATABASE mydb SET TABLESPACE secondary;
● ALTER TABLE mytable SET TABLESPACE secondary;

‫اطلاعاتی‬ ‫بانک‬ ‫ایجاد‬
CREATE DATABASE my_db
       TEMPLATE my_template_db
       OWNER ali
       TABLESPACE my_space
       ENCODING utf8;

DATABASE SCHEMA
● Schemas organize your database into logical groups
– Default schema is public.
– object names must be unique within a schema.
– Same name in different schemas.
– search_path = "$user", public in postgresql.conf
– GRANT ALL ON ALL TABLES IN SCHEMA public TO
mydb_admin WITH GRANT OPTION;
– GRANT SELECT, REFERENCES, TRIGGER ON ALL TABLES IN
SCHEMA my_schema TO PUBLIC;
– Backup & restore on schema.

Extensions
● addons can install in a PostgreSQL database to extend
functionality.
● SELECT * FROM pg_available_extensions;
● CREATE EXTENSION: create extension in each database.
CREATE EXTENSION fuzzystrmatch SCHEMA my_extensions;
● Pgxn utility Install extension on server.
● Cube extension .
● Ltree extension.

Backup and Restore
● Backup from Database ,schema , wildcard ,
exclude tables from backup , compress backup ,
text backup , binary backup
Example:
pg_dump h localhost p 5432 U someuser F c b v f mydb.backup mydb
pg_dump h localhost p 5432 U someuser C F p b v f mydb.backup mydb
pg_dump h localhost p 5432 U someuser F c b v t *.pay* f pay.backup
mydb
pg_dump h localhost p 5432 U someuser F c b v n hr n payroll f
hr.backup mydb
pg_dump h localhost p 5432 U someuser F c b v N public f
all_sch_except_pub.backup mydb

Backup and Restore
psql U postgres f myglobals.sql
psql U postgres set ON_ERROR_STOP=on f myglobals.sql
psql U postgres d mydb f select_objects.sql
pg_restore dbname=mydb jobs=4 verbose mydb.backup
pg_restore dbname=postgres create jobs=4 verbose mydb.backup

Foreign Data Wrapper(FDW)
CREATE EXTENSION file_fdw;
CREATE SERVER my_server FOREIGN DATA WRAPPER file_fdw;
CREATE FOREIGN TABLE
  mem_info (mydata VARCHAR(150))
  SERVER my_server
  OPTIONS (format 'csv', header 'true', filename '/proc/meminfo');

Mysql Foreign DataWrapper
CREATE EXTENSION mysql_fdw;
CREATE SERVER mysql_svr FOREIGN DATA WRAPPER mysql_fdw
  OPTIONS (address '127.0.0.1', port '3306');
CREATE FOREIGN TABLE local_students (
  stno character varying (10),
  fname character varying (50),
  lname character varying (100)
);
SERVER mysql_svr
  OPTIONS (query 'SELECT stno,fname,lname from students');
CREATE USER MAPPING FOR PUBLIC SERVER mysql_svr
  OPTIONS (username 'user', password 'password123');

Pgpool II
● Synchronous replication
● Load balancing, automatic failover, connection
● pooling etc.
● Collaborating with other replication tools
– Streaming replication, Slony-I

Pgpool basic idea
Postgresql Client
Primary
Read/write query
Read query
Read query
secondary
secondary
Read/write query
Pgpool
server

‫اول‬ ‫بخش‬ ‫پایان‬
‫شما‬ ‫توجه‬ ‫از‬ ‫تشکر‬ ‫با‬
‫مقدم‬ ‫اسدی‬ ‫بنی‬ ‫عباس‬
baniasadi@meedc.net
‫پاک‬ ‫دست‬ ‫محمد‬
m.dastpak@meedc.net

An Introduction to Postgresql

Recommended

More Related Content

What's hot (20)

Viewers also liked (20)

Similar to An Introduction to Postgresql (20)

More from عباس بني اسدي مقدم (20)

Recently uploaded (20)

An Introduction to Postgresql