1.
安装首先，我是使用mysql进行测试的，你的机器上需要安装mysql数据库。
然后执行：
gem install mysql
到rubyforge下载ruby-DBI,解压后cd到目录运行如下命令：
ruby setup.rb config --with=dbi,dbd_mysql
ruby setup.rb setup
ruby setup.rb install
完整的setup命令参数参考DBI的doc
2.完整例子DBI是一类似于ODBC的开发式的统一的数据库编程接口，结构层次上可以分为两层：
1.Database Interface——数据库接口层，与数据库无关，提供与数据库无关的标准接口
2.Database Driver——数据库驱动，与数据库相关
DBI也是很简单易用的，一个完整的使用例子，对于初学者可能有点帮助：
require
'
dbi
'
begin
#
连接数据库
dbh
=
DBI.connect(
"
DBI:Mysql:dbi_test:localhost
"
,
"
root
"
,
""
) dbh.columns(
"
simple
"
).each do
|
h
|
p h end
#
示范3种事务处理方式
#
手动commit
dbh[
"
AutoCommit
"
]
=
false
1
.upto(
10
) do
|
i
|
sql
=
"
insert into simple (name, author) VALUES (?, ?)
"
dbh.do(sql,
"
Song #{i}
"
,
"
#{i}
"
) end dbh.commit
#
使用transaction方法
dbh.transaction do
|
dbh
|
1
.upto(
10
) do
|
i
|
sql
=
"
insert into simple (name, author) VALUES (?, ?)
"
dbh.do(sql,
"
Song #{i}
"
,
"
#{i}
"
) end end
#
使用SQL语句
dbh.do(
"
SET AUTOCOMMIT=0
"
) dbh.do(
"
BEGIN
"
) dbh[
"
AutoCommit
"
]
=
false dbh.do(
"
UPDATE simple set name='test' where id='1'
"
) dbh.do(
"
COMMIT
"
)
#
查询
sth
=
dbh.execute(
"
select count(id) from simple
"
) puts
"
bookCount:#{sth.fetch[0]}
"
sth.finish begin sth
=
dbh.prepare(
"
select * from simple
"
) sth.execute
while
row
=
sth.fetch do p row end sth.finish rescue end
#
上面这段查询可以改写为：
#
dbh.select_all("select * from simple") do |row|
#
p row
#
end
#
使用工具类输出xml格式结果集以及测量查询时间
sql
=
"
select * from simple
"
mesuretime
=
DBI::Utils::measure do sth
=
dbh.execute(sql) end puts
"
SQL:#{sql}
"
puts
"
Time:#{mesuretime}
"
rows
=
sth.fetch_all col_names
=
sth.column_names sth.finish puts DBI::Utils::XMLFormatter.table(rows) dbh.do(
"
delete from simple
"
) rescue DBI::DatabaseError
=>
e puts
"
error code:#{e.err}
"
puts
"
Error message:#{e.errstr}
"
ensure dbh.disconnect
if
dbh end
文章转自庄周梦蝶 ，原文发布时间5.17
相关资源：敏捷开发V1.0.pptx
