ruby&sqlite的例子

q4561231

　　例子1


require 'sqlite'
db = SQLite::Database.new( "test.db" )
sql = <<SQL
drop table the_table;
create table the_table (
a varchar2(30),
b varchar2(30)
);
insert into the_table values ( 'one', 'two' );
insert into the_table values ( 'three', 'four' );
insert into the_table values ( 'five', 'six' );
SQL
db.execute_batch( sql )
db.results_as_hash = true
db.execute( "select * from the_table" ) do |row|
print row['a'], ',  ', row['b']
puts
end

　　

　　例子2


require 'sqlite'
require 'net/http'
def accessNet(stat, url)
res = Net::HTTP.get(URI.parse(URI.escape(url)))
res.gsub(/<[^>]*>/m, ' ').gsub(/[\r\n]/m, ' ').gsub(/'/m, '"').scan(/([a-zA-Z-]+)\s/).each do |v|
v = v.to_s.downcase
stat[v] = (stat[v]==nil) ? 1 : stat[v]+1
end
end
def saveData(db, stat)
sql, i = '', 0
stat.each do |k, v|
i = i+1
sql = "#{sql}insert into the_table values ('#{k}', #{v});"
if(i%1000==0)
db.transaction do |db|
db.execute_batch( sql )
end
sql=''
end
end
db.transaction do |db|
db.execute_batch( sql ) if(sql!='')
end
end

def doinit(db)
sql = <<SQL
drop table the_table;
create table the_table (
key varchar(300),
val int
);
SQL
db.execute_batch( sql )
end
def printInfo(db)
# do the select
db.results_as_hash = true
db.execute( "select * from the_table t order by t.val desc" ) do |row|
puts "#{row[0]}, #{row[1]}"
end
rows = db.execute( "select count(*) from the_table" )
p rows
end

db = SQLite::Database.new( "test.db" )
doinit db
stat = {}
accessNet(stat, 'http://www.chinadaily.com.cn/world/2011-08/12/content_13102444.htm')
accessNet(stat, 'http://www.chinadaily.com.cn/world/2011-08/12/content_13099183.htm')
accessNet(stat, 'http://www.chinadaily.com.cn/world/2011-08/13/content_13106532.htm')
accessNet(stat, 'http://www.chinadaily.com.cn/world/2011-08/14/content_13107273.htm')
accessNet(stat, 'http://www.chinadaily.com.cn/world/2011-08/12/content_13099653.htm')
accessNet(stat, 'http://www.chinadaily.com.cn/world/2011-08/14/content_13107262.htm')
accessNet(stat, 'http://www.chinadaily.com.cn/world/2011-08/15/content_13110160.htm')
saveData db, stat
printInfo db




　　相关的软件下载：
　　sqlite : http://www.sqlite.org/sqlitedll-2_8_17.zip
　　ruby gem : http://rubyforge.org/frs/?group_id=254&release_id=1522