Python:操作PostgreSQL数据库(使用DB API2.0)
游炳
昨天在《Python:操作PostgreSQL数据库(使用PyGreSQL)》一文中使用PyGreSQL模块实现了对PostgreSQL数据库的操作，今天使用另一种python通用的数据库访问接口DB API2.0来实现一下同样的操作，其实在《Python:操作嵌入式数据库SQLite》一文中我们使用的就是DB API2.0，我们可以看到，它对不同数据库提供了统一的访问接口，更多关于DB API2.0的介绍请参考http://www.python.org/dev/peps/pep-0249/
来看看实现，首先我们要下载提供DB API2.0接口的模块psycopg2,路径：http://initd.org/psycopg/download/，此模块API手册地址为：http://initd.org/psycopg/docs/index.html
一、实现：
#!/usr/bin/env python
# -*- coding: utf-8 -*-
#导入日志及psycopg2模块
import logging
import logging.config
import psycopg2
#日志配置文件名
LOG_FILENAME = 'logging.conf'
#日志语句提示信息
LOG_CONTENT_NAME = 'pg_log'
def log_init(log_config_filename, logname):
'''
Function:日志模块初始化函数
Input：log_config_filename:日志配置文件名
lognmae:每条日志前的提示语句
Output: logger
author: socrates
date:2012-02-13
'''
logging.config.fileConfig(log_config_filename)
logger = logging.getLogger(logname)
return logger
def operate_postgre_tbl_product():
'''
Function:操作pg数据库函数
Input：NONE
Output: NONE
author: socrates
date:2012-02-13
'''
pgdb_logger.debug("operate_postgre_tbl_product enter...")
#连接数据库
try:
pgdb_conn = psycopg2.connect(database = 'kevin_test', user = 'dyx1024', password = '888888', host = '192.168.230.128')
except Exception, e:
print e.args[0]
pgdb_logger.error("conntect postgre database failed, ret = %s" % e.args[0])
return
pgdb_logger.info("conntect postgre database(kevin_test) succ.")
pg_cursor = pgdb_conn.cursor()
#删除表
sql_desc = "DROP TABLE IF EXISTS tbl_product3;"
try:
pg_cursor.execute(sql_desc)
except Exception, e:
print 'drop table failed'
pgdb_logger.error("drop table failed, ret = %s" % e.args[0])
pg_cursor.close()
pgdb_conn.close()
return
pgdb_conn.commit()
pgdb_logger.info("drop table(tbl_product3) succ.")
#创建表
sql_desc = '''CREATE TABLE tbl_product3(
i_index INTEGER,
sv_productname VARCHAR(32)
);'''
try:
pg_cursor.execute(sql_desc)
except Exception, e:
print 'create table failed'
pgdb_logger.error("create table failed, ret = %s" % e.args[0])
pg_cursor.close()
pgdb_conn.close()
return
pgdb_conn.commit()
pgdb_logger.info("create table(tbl_product3) succ.")
#插入记录
sql_desc = "INSERT INTO tbl_product3(sv_productname) values('apple')"
try:
pg_cursor.execute(sql_desc)
except Exception, e:
print 'insert record into table failed'
pgdb_logger.error("insert record into table failed, ret = %s" % e.args[0])
pg_cursor.close()
pgdb_conn.close()
return
pgdb_conn.commit()
pgdb_logger.info("insert record into table(tbl_product3) succ.")
#查询表方法一
sql_desc = "select * from tbl_product3"
try:
pg_cursor.execute(sql_desc)
except Exception, e:
print 'select record from table tbl_product3 failed'
pgdb_logger.error("select record from table tbl_product3 failed, ret = %s" % e.args[0])
pg_cursor.close()
pgdb_conn.close()
return
for row in pg_cursor:
print row
pgdb_logger.info("%s", row)
print '*' * 20
#查询表方法二
sql_desc = "select * from tbl_test_port"
try:
pg_cursor.execute(sql_desc)
except Exception, e:
print 'select record from table tbl_test_port failed'
pgdb_logger.error("select record from table tbl_test_port failed, ret = %s" % e.args[0])
pg_cursor.close()
pgdb_conn.close()
return
for row in pg_cursor.fetchall():
print row
pgdb_logger.info("%s", row)
#关闭数据库连接
pg_cursor.close()
pgdb_conn.close()
pgdb_logger.debug("operate_sqlite3_tbl_product leaving...")
if __name__ == '__main__':
#初始化日志系统
pgdb_logger = log_init(LOG_FILENAME, LOG_CONTENT_NAME)
#操作数据库
operate_postgre_tbl_product()
二、测试：
1、命令行结果：
(None, 'apple')
********************
(1, 2, 1)
(2, 3, 1)
(3, 5, 1)
(5, 0, 1)
(7, 18, 1)
(8, 8, 1)
(9, 7, 1)
(10, 21, 1)
(11, 23, 1)
(12, 29, 1)
(4, 3000, 1)2、日志文件结果：
[2012-02-14 00:12:06,358 pg_log]DEBUG: operate_postgre_tbl_product enter... (db_postgre.py:36)
[2012-02-14 00:12:06,453 pg_log]INFO: conntect postgre database(kevin_test) succ. (db_postgre.py:46)
[2012-02-14 00:12:06,467 pg_log]INFO: drop table(tbl_product3) succ. (db_postgre.py:62)
[2012-02-14 00:12:06,483 pg_log]INFO: create table(tbl_product3) succ. (db_postgre.py:79)
[2012-02-14 00:12:06,483 pg_log]INFO: insert record into table(tbl_product3) succ. (db_postgre.py:93)
[2012-02-14 00:12:06,483 pg_log]INFO: (None, 'apple') (db_postgre.py:108)
[2012-02-14 00:12:06,483 pg_log]INFO: (1, 2, 1) (db_postgre.py:124)
[2012-02-14 00:12:06,483 pg_log]INFO: (2, 3, 1) (db_postgre.py:124)
[2012-02-14 00:12:06,483 pg_log]INFO: (3, 5, 1) (db_postgre.py:124)
[2012-02-14 00:12:06,483 pg_log]INFO: (5, 0, 1) (db_postgre.py:124)
[2012-02-14 00:12:06,483 pg_log]INFO: (7, 18, 1) (db_postgre.py:124)
[2012-02-14 00:12:06,500 pg_log]INFO: (8, 8, 1) (db_postgre.py:124)
[2012-02-14 00:12:06,500 pg_log]INFO: (9, 7, 1) (db_postgre.py:124)
[2012-02-14 00:12:06,500 pg_log]INFO: (10, 21, 1) (db_postgre.py:124)
[2012-02-14 00:12:06,500 pg_log]INFO: (11, 23, 1) (db_postgre.py:124)
[2012-02-14 00:12:06,500 pg_log]INFO: (12, 29, 1) (db_postgre.py:124)
[2012-02-14 00:12:06,500 pg_log]INFO: (4, 3000, 1) (db_postgre.py:124)
[2012-02-14 00:12:06,500 pg_log]INFO: (6, 1999, 1) (db_postgre.py:124)
[2012-02-14 00:12:06,500 pg_log]DEBUG: operate_sqlite3_tbl_product leaving... (db_postgre.py:130)
类似资料：