Update records ' and a.subscriber_id=b.subscriber_id; Connections select count(*) from pg_stat_activity; select client_addr,state,count(*) from pg_stat_activity group by client_addr,state order by count(*) desc; select max_conn,used,res_for_super,max…

1 PL/pgSQL Under the Hood This part discusses some implementation details that are frequently important for PL/pgSQL users to know. 1.1 Variable Substitution SQL statements and expressions within a PL/pgSQL function can refer to variables and paramet…

一.postgresql简介 postgresql是一款关系型数据库,广泛应用在web编程当中,由于其语法与MySQL不尽相同,所以其SQL注入又自成一派. 二.postgresql的SQL注入:(注意注释符号--+) 1.简单的有回显的SQL注入不用多说,还是基本的SQL语句直接查询就可以了. #简单的payload parameter = 2-1 parameter = 1 and 1 = 2 parameter = 1 or 1 = 2-1 parameter = 1' and '1'='…

Cursors Rather than executing a whole query at once, it is possible to set up a cursor that encapsulates the query, and then read the query result a few rows at a time. A more interesting usage is to return a reference to a cursor that a function has…

Control Structures of PL/SQL Control structures are probably the most useful (and important) part of PL/pgSQL.With PL/pgSQL's control structures, you can manipulate PostgreSQL data in a very flexible and powerful way. 1.Returning From a Function RETU…

查看服务进程: select pid,usename,client_addr,client_port from pg_stat_activity;   查看当前数据库实例的版本:  select version();    查看数据库的启动时间: select pg_postmaster_start_time();   查看最后load配置文件的时间: select pg_conf_load_time();   显示当前数据库时区: show timezone;   postgres=# sho…

PostgreSQL 8.1 轰动发布,我也打算将原来使用 SQL Server 的一些应用迁移到 PostgreSQL 上,首先需要迁移的是表,那么这就必须要先搞清楚这两个数据库中的数据类型的映射关系.查了下 PostgreSQL 文档特制作如下对应表格,以飨各位. 注意:PostgreSQL 中的 money(货币)数据类型现在已经废弃,用 numeric 或 decimal 以及和 to_char 函数一起使用就可以取代它. SQL Server 中的 datetime.smalldate…

最近开发一个WEB的ETL工具需要用到不同的数据源.第一次用POSTGRESQL发现一个双引号引发的问题: 标准的SQL是不区分大小写的.但是PostgreSQL对于数据库中对象的名字允许使用支持大小写区分的定义和引用方法.方式就是在DDL中用双引号把希望支持大小的对象名括起来.比如希望创建一个叫AAA的表.如果用CREATE TABLE AAA (...);的话,创建出来的表实际上是aaa.如果希望创建大写的AAA表的话,就需要用CREATE TABLE "AAA" (...);这种…

平时用的比较多的SQL语句,有时候会忘掉一点点,在这里记录一下: 1.创建表的同时,插入数据: create table test as select generate_series(1, 1000000) as id, cast(random() as text) as info , now() as crt_time; mydb=# create table test as select generate_series(1, 1000000) as id, cast(random() as…

1.Structure of PL/pgSQL The structure of PL/pgSQL is like below: [ <<label>> ] [ DECLARE declarations ] BEGIN statements END [ label ]; A label is only needed if you want to identify the block for use in an EXIT statement, or to qualify the na…