postgresql数据库-Perl连接PostgreSQL数据库

跨零代码为大家提供高品质的解决方案,请大家多多来访,跨零不胜感激,在此谢过。

PostgreSQL可以使用Perl DBI模块与Perl集成,Perl DBI模块是Perl编程语言的数据库访问模块。 它定义了一组提供标准数据库接口的方法,变量和约定。

以下是在Linux / Unix机器上安装DBI模块的简单步骤:

$ wget http://search.cpan.org/CPAN/authors/id/T/TI/TIMB/DBI-1.625.tar.gz $ tar xvfz DBI-1.625.tar.gz $ cd DBI-1.625 $ perl Makefile.PL $ make $ make install 

如果您需要安装DBI的SQLite驱动程序,那么可以安装如下:

$ wget http://search.cpan.org/CPAN/authors/id/T/TU/TURNSTEP/DBD-Pg-2.19.3.tar.gz $ tar xvfz DBD-Pg-2.19.3.tar.gz $ cd DBD-Pg-2.19.3 $ perl Makefile.PL $ make $ make install 

在开始使用Perl连接PostgreSQL接口之前,请在PostgreSQL安装目录中找到pg_hba.conf文件,并添加以下行:

# IPv4 local connections: host    all         all         127.0.0.1/32          md5 

您可以启动/重新启动postgres服务器,可使用以下命令运行:

[root@host]# service postgresql restart Stopping postgresql service:                               [  OK  ] Starting postgresql service:                               [  OK  ] 

Perl连接到PostgreSQL数据库

以下Perl代码显示如何连接到现有的数据库。 如果数据库不存在,那么它将自动创建,最后将返回一个数据库对象。

#!/usr/bin/perl  use DBI; use strict;  my $driver   = "Pg";  my $database = "testdb"; my $dsn = "DBI:$driver:dbname=$database;host=127.0.0.1;port=5432"; my $userid = "postgres"; my $password = "pass123"; my $dbh = DBI->connect($dsn, $userid, $password, { RaiseError => 1 })                        or die $DBI::errstr;  print "Opened database successfully/n"; 

现在,我们运行上面的程序来打开数据库:testdb,如果成功打开数据库,那么它将给出以下消息:

Open database successfully 

创建表

以下Perl程序将用于在之前创建的数据库(testdb)中创建一个表:

#!/usr/bin/perl  use DBI; use strict;  my $driver   = "Pg";  my $database = "testdb"; my $dsn = "DBI:$driver:dbname=$database;host=127.0.0.1;port=5432"; my $userid = "postgres"; my $password = "pass123"; my $dbh = DBI->connect($dsn, $userid, $password, { RaiseError => 1 })                       or die $DBI::errstr; print "Opened database successfully/n";  my $stmt = qq(CREATE TABLE COMPANY       (ID INT PRIMARY KEY     NOT NULL,        NAME           TEXT    NOT NULL,        AGE            INT     NOT NULL,        ADDRESS        CHAR(50),        SALARY         REAL);); my $rv = $dbh->do($stmt); if($rv < 0){    print $DBI::errstr; } else {    print "Table created successfully/n"; } $dbh->disconnect(); 

当执行上述程序时,它将在testdb中创建一张COMPANY表,并显示以下消息:

Opened database successfully Table created successfully 

插入操作

以下Perl程序显示了如何在上述示例中创建的COMPANY表中创建/插入记录:

#!/usr/bin/perl  use DBI; use strict;  my $driver   = "Pg";  my $database = "testdb"; my $dsn = "DBI:$driver:dbname=$database;host=127.0.0.1;port=5432"; my $userid = "postgres"; my $password = "pass123"; my $dbh = DBI->connect($dsn, $userid, $password, { RaiseError => 1 })                       or die $DBI::errstr; print "Opened database successfully/n";  my $stmt = qq(INSERT INTO COMPANY (ID,NAME,AGE,ADDRESS,SALARY)       VALUES (1, 'Paul', 32, 'California', 20000.00 )); my $rv = $dbh->do($stmt) or die $DBI::errstr;  $stmt = qq(INSERT INTO COMPANY (ID,NAME,AGE,ADDRESS,SALARY)       VALUES (2, 'Allen', 25, 'Texas', 15000.00 )); $rv = $dbh->do($stmt) or die $DBI::errstr;  $stmt = qq(INSERT INTO COMPANY (ID,NAME,AGE,ADDRESS,SALARY)       VALUES (3, 'Teddy', 23, 'Norway', 20000.00 )); $rv = $dbh->do($stmt) or die $DBI::errstr;  $stmt = qq(INSERT INTO COMPANY (ID,NAME,AGE,ADDRESS,SALARY)       VALUES (4, 'Mark', 25, 'Rich-Mond ', 65000.00 );); $rv = $dbh->do($stmt) or die $DBI::errstr;  print "Records created successfully/n"; $dbh->disconnect(); 

当执行上述程序时,它将在COMPANY表中创建/插入给定的记录,并显示以下两行:

Opened database successfully Records created successfully 

SELECT操作

以下Perl程序显示了如何从上述示例中创建的COMPANY表中获取和显示记录:

#!/usr/bin/perl  use DBI; use strict;  my $driver   = "Pg";  my $database = "testdb"; my $dsn = "DBI:$driver:dbname=$database;host=127.0.0.1;port=5432"; my $userid = "postgres"; my $password = "pass123"; my $dbh = DBI->connect($dsn, $userid, $password, { RaiseError => 1 })                       or die $DBI::errstr; print "Opened database successfully/n";  my $stmt = qq(SELECT id, name, address, salary  from COMPANY;); my $sth = $dbh->prepare( $stmt ); my $rv = $sth->execute() or die $DBI::errstr; if($rv < 0){    print $DBI::errstr; } while(my @row = $sth->fetchrow_array()) {       print "ID = ". $row[0] . "/n";       print "NAME = ". $row[1] ."/n";       print "ADDRESS = ". $row[2] ."/n";       print "SALARY =  ". $row[3] ."/n/n"; } print "Operation done successfully/n"; $dbh->disconnect(); 

执行上述程序时,会产生以下结果:

Opened database successfully ID = 1 NAME = Paul ADDRESS = California SALARY =  20000  ID = 2 NAME = Allen ADDRESS = Texas SALARY =  15000  ID = 3 NAME = Teddy ADDRESS = Norway SALARY =  20000  ID = 4 NAME = Mark ADDRESS = Rich-Mond SALARY =  65000  Operation done successfully 

更新操作

Perl代码显示了如何使用UPDATE语句来更新指定记录,然后从COMPANY表中获取和显示更新的记录:

#!/usr/bin/perl  use DBI; use strict;  my $driver   = "Pg";  my $database = "testdb"; my $dsn = "DBI:$driver:dbname=$database;host=127.0.0.1;port=5432"; my $userid = "postgres"; my $password = "pass123"; my $dbh = DBI->connect($dsn, $userid, $password, { RaiseError => 1 })                       or die $DBI::errstr; print "Opened database successfully/n";  my $stmt = qq(UPDATE COMPANY set SALARY = 25000.00 where ID=1;); my $rv = $dbh->do($stmt) or die $DBI::errstr; if( $rv < 0 ){    print $DBI::errstr; }else{    print "Total number of rows updated : $rv/n"; } $stmt = qq(SELECT id, name, address, salary  from COMPANY;); my $sth = $dbh->prepare( $stmt ); $rv = $sth->execute() or die $DBI::errstr; if($rv < 0){    print $DBI::errstr; } while(my @row = $sth->fetchrow_array()) {       print "ID = ". $row[0] . "/n";       print "NAME = ". $row[1] ."/n";       print "ADDRESS = ". $row[2] ."/n";       print "SALARY =  ". $row[3] ."/n/n"; } print "Operation done successfully/n"; $dbh->disconnect(); 

执行上述程序时,会产生以下结果:

Opened database successfully Total number of rows updated : 1 ID = 1 NAME = Paul ADDRESS = California SALARY =  25000  ID = 2 NAME = Allen ADDRESS = Texas SALARY =  15000  ID = 3 NAME = Teddy ADDRESS = Norway SALARY =  20000  ID = 4 NAME = Mark ADDRESS = Rich-Mond SALARY =  65000  Operation done successfully 

删除操作

Perl代码显示了如何使用DELETE语句删除指定记录,然后从COMPANY表中获取并显示剩余的记录:

#!/usr/bin/perl  use DBI; use strict;  my $driver   = "Pg";  my $database = "testdb"; my $dsn = "DBI:$driver:dbname=$database;host=127.0.0.1;port=5432"; my $userid = "postgres"; my $password = "pass123"; my $dbh = DBI->connect($dsn, $userid, $password, { RaiseError => 1 })                       or die $DBI::errstr; print "Opened database successfully/n";  my $stmt = qq(DELETE from COMPANY where ID=2;); my $rv = $dbh->do($stmt) or die $DBI::errstr; if( $rv < 0 ){    print $DBI::errstr; }else{    print "Total number of rows deleted : $rv/n"; } $stmt = qq(SELECT id, name, address, salary  from COMPANY;); my $sth = $dbh->prepare( $stmt ); $rv = $sth->execute() or die $DBI::errstr; if($rv < 0){    print $DBI::errstr; } while(my @row = $sth->fetchrow_array()) {       print "ID = ". $row[0] . "/n";       print "NAME = ". $row[1] ."/n";       print "ADDRESS = ". $row[2] ."/n";       print "SALARY =  ". $row[3] ."/n/n"; } print "Operation done successfully/n"; $dbh->disconnect(); 

执行上述程序时,会产生以下结果:

Opened database successfully Total number of rows deleted : 1 ID = 1 NAME = Paul ADDRESS = California SALARY =  25000  ID = 3 NAME = Teddy ADDRESS = Norway SALARY =  20000  ID = 4 NAME = Mark ADDRESS = Rich-Mond SALARY =  65000  Operation done successfully 

  

上一篇: PHP连接PostgreSQL数据库 下一篇: Python连接PostgreSQL数据库

加QQ群啦,易百教程官方技术学习群

从零到一,创造未来!跨零综合IT问题解决服务站,欢迎你的到来。Oracle数据库教程 postgresql数据库/a> 只为你绽放。

本文固定链接: http://kua0.com/2019/11/11/postgresql数据库-perl连接postgresql数据库/

为您推荐

发表评论

电子邮件地址不会被公开。 必填项已用*标注