安装psycopg2模块：

postgresql client ---Navicat Premium

怎么验证是否已经安装过psycopy2?

编写上面代码，运行看是否抛出缺少psycopg2模块。

安装方法1：

1)使用psycopg2-2.4.2.win-amd64-py2.7-pg9.0.4-release.exe安装，下载地址:http://vdisk.weibo.com/s/Cd8pPaw56Ozys

直接运行exe，不出错误，运行上边代码验证代码无错误，基本算是安装完成了。

2)怎么卸载？

2.1)找到安装目录：C:\Python27，发现下边包含文件:Removepsycopg2.exe,运行，来删除；

2.2)如果运行失败的话，进入目录：C:\Python27\Lib\site-packages下，找到psycopg2文件夹和psycopg2-2.4.2-py2.7.egg-info文件，右键删除。

2.3)运行上边的代码，确认是否删除成功。

安装方法2：

使用.whl安装，下载地址：https://pypi.python.org/pypi/psycopg2/

下载文件：psycopg2-2.6.2-cp27-none-win_amd64.whl

我这里把psycopg2-2.6.2-cp27-none-win_amd64.whl拷贝到安装目录下Scripts文件夹中。

cmd中运行代码：pip install C:\Python27\Scripts\psycopg2-2.6.2-cp27-none-win_amd64.whl

运行上边的代码，确认是否删除成功。

通过psycopg2操作数据库：

使用账户postgres，创建测试数据库testdb。

参考yiibai.comAPI:

S.N. API & 描述

1psycopg2.connect(database="testdb", user="postgres", password="cohondob", host="127.0.0.1", port="5432")

这个API打开一个连接到PostgreSQL数据库。如果成功打开数据库时，它返回一个连接对象。

2connection.cursor()

该程序创建一个光标将用于整个数据库使用Python编程。

3cursor.execute(sql [, optional parameters])

此例程执行SQL语句。可被参数化的SQL语句(即占位符，而不是SQL文字)。 psycopg2的模块支持占位符用％s标志

例如：cursor.execute("insert into people values (%s, %s)", (who, age))

4curosr.executemany(sql, seq_of_parameters)

该程序执行SQL命令对所有参数序列或序列中的sql映射。

5curosr.callproc(procname[, parameters])

这个程序执行的存储数据库程序给定的名称。该程序预计为每一个参数，参数的顺序必须包含一个条目。

6cursor.rowcount

这个只读属性，它返回数据库中的行的总数已修改，插入或删除最后 execute*().

7connection.commit()

此方法提交当前事务。如果不调用这个方法，无论做了什么修改，自从上次调用commit()是不可见的，从其他的数据库连接。

8connection.rollback()

此方法会回滚任何更改数据库自上次调用commit()方法。

9connection.close()

此方法关闭数据库连接。请注意，这并不自动调用commit()。如果你只是关闭数据库连接而不调用commit()方法首先，那么所有更改将会丢失！

10cursor.fetchone()

这种方法提取的查询结果集的下一行，返回一个序列，或者无当没有更多的数据是可用的。

11cursor.fetchmany([size=cursor.arraysize])

这个例程中取出下一个组的查询结果的行数，返回一个列表。当没有找到记录，返回空列表。该方法试图获取尽可能多的行所显示的大小参数。

12cursor.fetchall()

这个例程获取所有查询结果(剩余)行，返回一个列表。空行时则返回空列表。

打开数据库连接：

1 importos2 importsys3 importpsycopg24

5 defconnectPostgreSQL():6 conn = psycopg2.connect(database="testdb", user="postgres", password="new.1234", host="127.0.0.1", port="5432")7 print 'connect successful!'

8

9 if __name__=='__main__':10 connectPostgreSQL()11

创建表操作：

1 importos2 importsys3 importpsycopg24

5 defconnectPostgreSQL():6 conn = psycopg2.connect(database="testdb", user="postgres", password="new.1234", host="127.0.0.1", port="5432")7 print 'connect successful!'

8 cursor=conn.cursor()9 cursor.execute('''create table public.member(10 id integer not null primary key,11 name varchar(32) not null,12 password varchar(32) not null,13 singal varchar(128)14 )''')15 conn.commit()16 conn.close()17 print 'table public.member is created!'

18

19 if __name__=='__main__':20 connectPostgreSQL()21

Insert 操作：

1 importos2 importsys3 importpsycopg24

5 defconnectPostgreSQL():6 conn = psycopg2.connect(database="testdb", user="postgres", password="new.1234", host="127.0.0.1", port="5432")7 print 'connect successful!'

8 cursor=conn.cursor()9 cursor.execute('''create table public.member(10 id integer not null primary key,11 name varchar(32) not null,12 password varchar(32) not null,13 singal varchar(128)14 )''')15 conn.commit()16 conn.close()17 print 'table public.member is created!'

18

19 definsertOperate():20 conn = psycopg2.connect(database="testdb", user="postgres", password="new.1234", host="127.0.0.1", port="5432")21 cursor=conn.cursor()22 cursor.execute("insert into public.member(id,name,password,singal)\23 values(1,'member0','password0','signal0')")24 cursor.execute("insert into public.member(id,name,password,singal)\25 values(2,'member1','password1','signal1')")26 cursor.execute("insert into public.member(id,name,password,singal)\27 values(3,'member2','password2','signal2')")28 cursor.execute("insert into public.member(id,name,password,singal)\29 values(4,'member3','password3','signal3')")30 conn.commit()31 conn.close()32

33 print 'insert records into public.memmber successfully'

34

35 if __name__=='__main__':36 #connectPostgreSQL()

37 insertOperate()38

Select 操作：

1 importos2 importsys3 importpsycopg24

5 defconnectPostgreSQL():6 conn = psycopg2.connect(database="testdb", user="postgres", password="new.1234", host="127.0.0.1", port="5432")7 print 'connect successful!'

8 cursor=conn.cursor()9 cursor.execute('''create table public.member(10 id integer not null primary key,11 name varchar(32) not null,12 password varchar(32) not null,13 singal varchar(128)14 )''')15 conn.commit()16 conn.close()17 print 'table public.member is created!'

18

19 definsertOperate():20 conn = psycopg2.connect(database="testdb", user="postgres", password="new.1234", host="127.0.0.1", port="5432")21 cursor=conn.cursor()22 cursor.execute("insert into public.member(id,name,password,singal)\23 values(1,'member0','password0','signal0')")24 cursor.execute("insert into public.member(id,name,password,singal)\25 values(2,'member1','password1','signal1')")26 cursor.execute("insert into public.member(id,name,password,singal)\27 values(3,'member2','password2','signal2')")28 cursor.execute("insert into public.member(id,name,password,singal)\29 values(4,'member3','password3','signal3')")30 conn.commit()31 conn.close()32

33 print 'insert records into public.memmber successfully'

34

35 defselectOperate():36 conn = psycopg2.connect(database="testdb", user="postgres", password="new.1234", host="127.0.0.1", port="5432")37 cursor=conn.cursor()38 cursor.execute("select id,name,password,singal from public.member where id>2")39 rows=cursor.fetchall()40 for row inrows:41 print 'id=',row[0], ',name=',row[1],',pwd=',row[2],',singal=',row[3],'\n'

42 conn.close()43

44 if __name__=='__main__':45 #connectPostgreSQL()

46 #insertOperate()

47 selectOperate()48

结果：

Python 2.7.12 (v2.7.12:d33e0cf91556, Jun 27 2016, 15:24:40) [MSC v.1500 64bit (AMD64)] on win32

Type"copyright", "credits" or "license()" formore information.>>>

========== RESTART: C:\Users\Administrator\Desktop\mutilpleTest.py ==========id= 3 ,name= member2 ,pwd= password2 ,singal=signal2

id= 4 ,name= member3 ,pwd= password3 ,singal=signal3>>>

update操作：

1 importos2 importsys3 importpsycopg24

5 defconnectPostgreSQL():6 conn = psycopg2.connect(database="testdb", user="postgres", password="new.1234", host="127.0.0.1", port="5432")7 print 'connect successful!'

8 cursor=conn.cursor()9 cursor.execute('''create table public.member(10 id integer not null primary key,11 name varchar(32) not null,12 password varchar(32) not null,13 singal varchar(128)14 )''')15 conn.commit()16 conn.close()17 print 'table public.member is created!'

18

19 definsertOperate():20 conn = psycopg2.connect(database="testdb", user="postgres", password="new.1234", host="127.0.0.1", port="5432")21 cursor=conn.cursor()22 cursor.execute("insert into public.member(id,name,password,singal)\23 values(1,'member0','password0','signal0')")24 cursor.execute("insert into public.member(id,name,password,singal)\25 values(2,'member1','password1','signal1')")26 cursor.execute("insert into public.member(id,name,password,singal)\27 values(3,'member2','password2','signal2')")28 cursor.execute("insert into public.member(id,name,password,singal)\29 values(4,'member3','password3','signal3')")30 conn.commit()31 conn.close()32

33 print 'insert records into public.memmber successfully'

34

35 defselectOperate():36 conn = psycopg2.connect(database="testdb", user="postgres", password="new.1234", host="127.0.0.1", port="5432")37 cursor=conn.cursor()38 cursor.execute("select id,name,password,singal from public.member where id>2")39 rows=cursor.fetchall()40 for row inrows:41 print 'id=',row[0], ',name=',row[1],',pwd=',row[2],',singal=',row[3],'\n'

42 conn.close()43

44 defupdateOperate():45 conn = psycopg2.connect(database="testdb", user="postgres", password="new.1234", host="127.0.0.1", port="5432")46 cursor=conn.cursor()47 cursor.execute("update public.member set name='update ...' where id=2")48 conn.commit()49 print "Total number of rows updated :", cursor.rowcount50

51 cursor.execute("select id,name,password,singal from public.member")52 rows=cursor.fetchall()53 for row inrows:54 print 'id=',row[0], ',name=',row[1],',pwd=',row[2],',singal=',row[3],'\n'

55 conn.close()56

57 if __name__=='__main__':58 #connectPostgreSQL()

59 #insertOperate()

60 #selectOperate()

61 updateOperate()

结果：

Python 2.7.12 (v2.7.12:d33e0cf91556, Jun 27 2016, 15:24:40) [MSC v.1500 64bit (AMD64)] on win32

Type"copyright", "credits" or "license()" formore information.>>>

========== RESTART: C:\Users\Administrator\Desktop\mutilpleTest.py ==========Total number of rows updated :1id= 1 ,name= member0 ,pwd= password0 ,singal=signal0

id= 3 ,name= member2 ,pwd= password2 ,singal=signal2

id= 4 ,name= member3 ,pwd= password3 ,singal=signal3

id= 2 ,name= update ... ,pwd= password1 ,singal=signal1>>>

Delete操作：

1 importos2 importsys3 importpsycopg24

5 defconnectPostgreSQL():6 conn = psycopg2.connect(database="testdb", user="postgres", password="new.1234", host="127.0.0.1", port="5432")7 print 'connect successful!'

8 cursor=conn.cursor()9 cursor.execute('''create table public.member(10 id integer not null primary key,11 name varchar(32) not null,12 password varchar(32) not null,13 singal varchar(128)14 )''')15 conn.commit()16 conn.close()17 print 'table public.member is created!'

18

19 definsertOperate():20 conn = psycopg2.connect(database="testdb", user="postgres", password="new.1234", host="127.0.0.1", port="5432")21 cursor=conn.cursor()22 cursor.execute("insert into public.member(id,name,password,singal)\23 values(1,'member0','password0','signal0')")24 cursor.execute("insert into public.member(id,name,password,singal)\25 values(2,'member1','password1','signal1')")26 cursor.execute("insert into public.member(id,name,password,singal)\27 values(3,'member2','password2','signal2')")28 cursor.execute("insert into public.member(id,name,password,singal)\29 values(4,'member3','password3','signal3')")30 conn.commit()31 conn.close()32

33 print 'insert records into public.memmber successfully'

34

35 defselectOperate():36 conn = psycopg2.connect(database="testdb", user="postgres", password="new.1234", host="127.0.0.1", port="5432")37 cursor=conn.cursor()38 cursor.execute("select id,name,password,singal from public.member where id>2")39 rows=cursor.fetchall()40 for row inrows:41 print 'id=',row[0], ',name=',row[1],',pwd=',row[2],',singal=',row[3],'\n'

42 conn.close()43

44 defupdateOperate():45 conn = psycopg2.connect(database="testdb", user="postgres", password="new.1234", host="127.0.0.1", port="5432")46 cursor=conn.cursor()47 cursor.execute("update public.member set name='update ...' where id=2")48 conn.commit()49 print "Total number of rows updated :", cursor.rowcount50

51 cursor.execute("select id,name,password,singal from public.member")52 rows=cursor.fetchall()53 for row inrows:54 print 'id=',row[0], ',name=',row[1],',pwd=',row[2],',singal=',row[3],'\n'

55 conn.close()56

57 defdeleteOperate():58 conn = psycopg2.connect(database="testdb", user="postgres", password="new.1234", host="127.0.0.1", port="5432")59 cursor=conn.cursor()60

61 cursor.execute("select id,name,password,singal from public.member")62 rows=cursor.fetchall()63 for row inrows:64 print 'id=',row[0], ',name=',row[1],',pwd=',row[2],',singal=',row[3],'\n'

65

66 print 'begin delete'

67 cursor.execute("delete from public.member where id=2")68 conn.commit()69 print 'end delete'

70 print "Total number of rows deleted :", cursor.rowcount71

72 cursor.execute("select id,name,password,singal from public.member")73 rows=cursor.fetchall()74 for row inrows:75 print 'id=',row[0], ',name=',row[1],',pwd=',row[2],',singal=',row[3],'\n'

76 conn.close()77

78 if __name__=='__main__':79 #connectPostgreSQL()

80 #insertOperate()

81 #selectOperate()

82 #updateOperate()

83 deleteOperate()

结果：

Python 2.7.12 (v2.7.12:d33e0cf91556, Jun 27 2016, 15:24:40) [MSC v.1500 64bit (AMD64)] on win32

Type"copyright", "credits" or "license()" formore information.>>>

========== RESTART: C:\Users\Administrator\Desktop\mutilpleTest.py ==========id= 1 ,name= member0 ,pwd= password0 ,singal=signal0

id= 3 ,name= member2 ,pwd= password2 ,singal=signal2

id= 4 ,name= member3 ,pwd= password3 ,singal=signal3

id= 2 ,name= update ... ,pwd= password1 ,singal=signal1

begin delete

end delete

Total number of rows deleted :1id= 1 ,name= member0 ,pwd= password0 ,singal=signal0

id= 3 ,name= member2 ,pwd= password2 ,singal=signal2

id= 4 ,name= member3 ,pwd= password3 ,singal=signal3>>>

参考文章：

http://www.cnblogs.com/qiongmiaoer/archive/2013/09/30/3346984.html

http://www.yiibai.com/html/postgresql/2013/080998.html