require "dbi"
dbh = DBI.connect("DBI:ODBC:#{db_name}",@user,@password)
sth = dbh.execute(%%1)
提取单条记录
# @database is array of references to anonymous hashes
@database = (
{ name =>"Wild Ginger",
city =>"Seattle",
cuisine =>"Asian Thai Chinese Korean Japanese",
expense =>4,
music =>"\0",
meals =>"lunch dinner",
view =>"\0",
smoking =>"\0",
parking =>"validated",
rating=>4,
payment =>"MC VISA AMEX",
},
# { ... }, etc.
)
sub findRestaurants {
my ($database, $query) = @_
return grep {
$query->{city} ?
lc($query->{city}) eq lc($_->{city}) : 1
and $query->{cuisine} ?
$_->{cuisine} =~ /$query->{cuisine}/i : 1
and $query->{min_expense} ?
$_->{expense} >= $query->{min_expense} : 1
and $query->{max_expense} ?
$_->{expense} <= $query->{max_expense} : 1
and $query->{music} ? $_->{music} : 1
and $query->{music_type} ?
$_->{music} =~ /$query->{music_type}/i : 1
and $query->{meals} ?
$_->{meals} =~ /$query->{meals}/i : 1
and $query->{view} ? $_->{view} : 1
and $query->{smoking} ? $_->{smoking} : 1
and $query->{parking} ? $_->{parking} : 1
and $query->{min_rating} ?
$_->{rating} >= $query->{min_rating} : 1
and $query->{max_rating} ?
$_->{rating} <= $query->{max_rating} : 1
and $query->{payment} ?
$_->{payment} =~ /$query->{payment}/i : 1
} @$database
}
1、内存数据产生
2、产生xml内存对象(也就是DOM树)
3、产生根对象
4、往根对象里加数据
5、把xml内存对象写到文件
下面是一个创建xml文档的简单实例:
import xml.dom.minidom#在内存中创建一个空的文档doc = xml.dom.minidom.Document()#创建一个根节点Managers对象root = doc.createElement('Managers')
#设置根节点的属性root.setAttribute('company', 'xx科技')
root.setAttribute('address', '科技软件园')
#将根节点添加到文档对象中doc.appendChild(root)
managerList = [{'name' : 'joy', 'age' : 27, 'sex' : '女'},
{'name' : 'tom', 'age' : 30, 'sex' : '男'},
{'name' : 'ruby', 'age' : 29, 'sex' : '女'}
]for i in managerList :
nodeManager = doc.createElement('Manager')
nodeName = doc.createElement('name')
#给叶子节点name设置一个文本节点,用于显示文本内容
nodeName.appendChild(doc.createTextNode(str(i['name'])))
nodeAge = doc.createElement("age")
nodeAge.appendChild(doc.createTextNode(str(i["age"])))
nodeSex = doc.createElement("sex")
nodeSex.appendChild(doc.createTextNode(str(i["sex"])))
#将各叶子节点添加到父节点Manager中,
#最后将Manager添加到根节点Managers中
nodeManager.appendChild(nodeName)
nodeManager.appendChild(nodeAge)
nodeManager.appendChild(nodeSex)
root.appendChild(nodeManager)#开始写xml文档fp = open('c:\\wcx\\Manager.xml', 'w')
doc.writexml(fp, indent='\t', addindent='\t', newl='\n', encoding="utf-8")
执行结果:
<?xml version="1.0" encoding="utf-8"?><Managers address="科技软件园" company="xx科技">
<Manager>
<name>joy</name>
<age>27</age>
<sex>女</sex>
</Manager>
<Manager>
<name>tom</name>
<age>30</age>
<sex>男</sex>
</Manager>
<Manager>
<name>ruby</name>
<age>29</age>
<sex>女</sex>
</Manager>
</Managers>
6.用Python自带的写xml文档的API去写,比较方便,后期容易维护。如果直接用打开文件的方式,一行一行的去写,比较费时,也难以维护。