rails:3369


前川です。

rubyメーリングにも投稿しましたが、反応がありませんでした。

mysqlのデータをdbiを使用して取得したいのですが、
("SELECT * FROM aplist")を実行すると、Segmentation faultが発生します。

ググってみたら、

http://rubyforge.org/tracker/index.php?func=detail&aid=26791&group_id=234&atid=967

に、同様のレポートがありましたが、解決していないのでしょうか？
どなたか、ご存知でしたら、ご教示ください。

パソコンの設定で、発生したり、しなかったりする？？

テーブル名(show tables)、db名("show databases")の取得は、
問題なく実行できます。

よろしくお願いします。


バージョンは、以下です。
C:\>ruby -v
ruby 1.8.7 (2010-01-10 patchlevel 249) [i386-mswin32]

MySQL;;5.1

C:\>gem list --local

*** LOCAL GEMS ***

actionmailer (2.3.4)
actionpack (2.3.4)
activerecord (2.3.4)
activeresource (2.3.4)
activesupport (2.3.4)
deprecated (2.0.1)
linecache (0.43)
mysql (2.8.1)
rack (1.0.0)
rails (2.3.4)
rake (0.8.7)
ruby-debug-base (0.10.3)
ruby-debug-ide (0.4.5)
sinatra (0.9.4)
sqlite3-ruby (1.2.5)

ソースコード

#!D:/Ruby/bin/ruby.exe -Ks

require "dbi"

begin
  #dbh = DBI.connect('DBI:Mysql:fbsys:a28341', 'dbuser01', 'dbkey')
  dbh = DBI.connect("DBI:Mysql:fbsys:localhost", "root", "dbkey")
  #sth = dbh.prepare("SHOW TABLES") #←OK
  sth = dbh.prepare("SELECT * FROM aplist")
  #sth = dbh.prepare("SHOW COLUMNS FROM aplist")
  #sth = dbh.prepare('DESCRIBE aplist')
  #sth = dbh.prepare("show databases") #OK
  puts dbh
  puts sth
  sth.execute
  puts 'count='+sth.rows.to_s #テーブル数のみ有効？

  count = 0
  sth.fetch { |row|
    p row
    count = count + 1
  }
  sth.finish
  puts 'increment count='+count.to_s
#DB例外発生時の処理
rescue DBI::DatabaseError => e
  p "An error occurred"
  p "Error code: #{e.err}"
  p "Error message: #{e.errstr}"
  #切断漏れしないようにensureでdisconnectします。
ensure
  dbh.disconnect if dbh
end

デバッガでの実行結果
すべて、step　(s)　で実行しました。
#以下、デバッガでの実施結果　162行ほどあります。冗長とは思いましたが、
#すべて、貼り付けました。

D:\Apache2.2\htdocs\ruby_prg\em_ruby\em_db>ruby -r debug
dbi_mysql_connect.rb
Debug.rb
Emacs support available.

dbi_mysql_connect.rb:3:require "dbi"
(rdb:1) l
[-2, 7] in dbi_mysql_connect.rb
   1
   2
=> 3  require "dbi"
   4
   5  begin
   6    #dbh = DBI.connect('DBI:Mysql:fbsys:a28341', 'dbuser01', 'dbkey')
   7    dbh = DBI.connect("DBI:Mysql:fbsys:localhost", "root", "dbkey")
(rdb:1) b 15
Set breakpoint 1 at dbi_mysql_connect.rb:15
(rdb:1) b
Breakpoints:
  1 dbi_mysql_connect.rb:15

(rdb:1) l
[8, 17] in dbi_mysql_connect.rb
   8    #sth = dbh.prepare("SHOW TABLES") #←OK
   9    sth = dbh.prepare("SELECT * FROM aplist")
   10    #sth = dbh.prepare("SHOW COLUMNS FROM aplist")
   11    #sth = dbh.prepare('DESCRIBE aplist')
   12    #sth = dbh.prepare("show databases") #OK
   13    puts dbh
   14    puts sth
   15    sth.execute
   16    puts 'count='+sth.rows.to_s #テーブル数のみ有効？
   17
(rdb:1) c
D:/Ruby/lib/ruby/1.8/rational.rb:78: `undefined method `gcd' for
Rational(1, 2):Rational' (NoMethodError)
        from D:/Ruby/lib/ruby/site_ruby/1.8/dbi.rb:39:in `require'
        from D:/Ruby/lib/ruby/site_ruby/1.8/dbi.rb:39
        from dbi_mysql_connect.rb:3:in `require'
        from dbi_mysql_connect.rb:3
D:/Ruby/lib/ruby/1.8/rational.rb:78:    gcd = num.gcd(den)
(rdb:1) w
--> #1 D:/Ruby/lib/ruby/1.8/rational.rb:78:in `reduce'
    #2 D:/Ruby/lib/ruby/1.8/rational.rb:35:in `Rational'
    #3 D:/Ruby/lib/ruby/1.8/date.rb:517
    #4 D:/Ruby/lib/ruby/1.8/date.rb:230
(rdb:1) c
#<DBI::DatabaseHandle:0x3b2ea14>
#<DBI::StatementHandle:0x3b2a450>
Breakpoint 1, toplevel at dbi_mysql_connect.rb:15
dbi_mysql_connect.rb:15:  sth.execute
(rdb:1) w
--> #1 dbi_mysql_connect.rb:15
(rdb:1) s
D:/Ruby/lib/ruby/site_ruby/1.8/dbi/handles/statement.rb:108:
cancel     # cancel before
(rdb:1) s
D:/Ruby/lib/ruby/site_ruby/1.8/dbi/handles/statement.rb:147:
sanity_check
(rdb:1) s
D:/Ruby/lib/ruby/site_ruby/1.8/dbi/handles/statement.rb:372:
raise InterfaceError, "Statement was already

closed!" if @
handle.nil?
(rdb:1) s
D:/Ruby/lib/ruby/site_ruby/1.8/dbi/handles/statement.rb:372:
raise InterfaceError, "Statement was already

closed!" if @
handle.nil?
(rdb:1) s
D:/Ruby/lib/ruby/site_ruby/1.8/dbi/handles/statement.rb:374:
params.each_key do |key|
(rdb:1) s
D:/Ruby/lib/ruby/site_ruby/1.8/dbi/handles/statement.rb:148:
@handle.cancel if @fetchable
(rdb:1) s
D:/Ruby/lib/ruby/site_ruby/1.8/dbi/handles/statement.rb:148:
@handle.cancel if @fetchable
(rdb:1) s
D:/Ruby/lib/ruby/site_ruby/1.8/dbi/handles/statement.rb:149:
@fetchable = false
(rdb:1) s
D:/Ruby/lib/ruby/site_ruby/1.8/dbi/handles/statement.rb:109:
sanity_check({:prepared => true })
(rdb:1) s
D:/Ruby/lib/ruby/site_ruby/1.8/dbi/handles/statement.rb:372:
raise InterfaceError, "Statement was already

closed!" if @
handle.nil?
(rdb:1) s
D:/Ruby/lib/ruby/site_ruby/1.8/dbi/handles/statement.rb:372:
raise InterfaceError, "Statement was already

closed!" if @
handle.nil?
(rdb:1) s
D:/Ruby/lib/ruby/site_ruby/1.8/dbi/handles/statement.rb:374:
params.each_key do |key|
(rdb:1) s
D:/Ruby/lib/ruby/site_ruby/1.8/dbi/handles/statement.rb:375:
case key
(rdb:1) s
D:/Ruby/lib/ruby/site_ruby/1.8/dbi/handles/statement.rb:376:
when :fetchable
(rdb:1) s
D:/Ruby/lib/ruby/site_ruby/1.8/dbi/handles/statement.rb:378:
when :executed
(rdb:1) s
D:/Ruby/lib/ruby/site_ruby/1.8/dbi/handles/statement.rb:380:
when :prepared
(rdb:1) s
D:/Ruby/lib/ruby/site_ruby/1.8/dbi/handles/statement.rb:381:
check_prepared
(rdb:1) s
D:/Ruby/lib/ruby/site_ruby/1.8/dbi/handles/statement.rb:389:
raise InterfaceError, "Statement wasn't prepared

before."
unless @prepared
(rdb:1) s
D:/Ruby/lib/ruby/site_ruby/1.8/dbi/handles/statement.rb:389:
raise InterfaceError, "Statement wasn't prepared

before."
unless @prepared
(rdb:1) s
D:/Ruby/lib/ruby/site_ruby/1.8/dbi/handles/statement.rb:111:            if
@convert_types
(rdb:1) s
D:/Ruby/lib/ruby/site_ruby/1.8/dbi/handles/statement.rb:111:            if
@convert_types
(rdb:1) s
D:/Ruby/lib/ruby/site_ruby/1.8/dbi/handles/statement.rb:112:
bindvars = DBI::Utils::ConvParam.conv_param

(dbh.driver
_name, *bindvars)
(rdb:1) s
D:/Ruby/lib/ruby/site_ruby/1.8/dbi/handles/database.rb:18:
return @driver_name.dup if @driver_name
(rdb:1) s
D:/Ruby/lib/ruby/site_ruby/1.8/dbi/handles/database.rb:18:
return @driver_name.dup if @driver_name
(rdb:1) s
D:/Ruby/lib/ruby/site_ruby/1.8/dbi/utils.rb:52:        params.collect {
|param| DBI::TypeUtil.convert(driver_name, param) }
(rdb:1) s
D:/Ruby/lib/ruby/site_ruby/1.8/dbi/handles/statement.rb:115:
@handle.bind_params(*bindvars)
(rdb:1) s
D:/Ruby/lib/ruby/site_ruby/1.8/dbi/base_classes/statement.rb:75:
bindvars.each_with_index {|val,i| bind_param

(i+1, val,
 nil) }
(rdb:1) s
D:/Ruby/lib/ruby/site_ruby/1.8/dbi/base_classes/statement.rb:76:
self
(rdb:1) s
D:/Ruby/lib/ruby/site_ruby/1.8/dbi/handles/statement.rb:116:
@handle.execute
(rdb:1) s
D:/Ruby/lib/ruby/site_ruby/1.8/dbd/mysql/statement.rb:33:            sql =
@prep_stmt.bind(@params)
(rdb:1) s
D:/Ruby/lib/ruby/site_ruby/1.8/dbi/sql/preparedstatement.rb:63:
if @arg_index < args.size
(rdb:1) s
D:/Ruby/lib/ruby/site_ruby/1.8/dbi/sql/preparedstatement.rb:63:
if @arg_index < args.size
(rdb:1) s
D:/Ruby/lib/ruby/site_ruby/1.8/dbi/sql/preparedstatement.rb:65:
elsif @arg_index > args.size
(rdb:1) s
D:/Ruby/lib/ruby/site_ruby/1.8/dbi/sql/preparedstatement.rb:69:
@unbound.each do |res_pos, arg_pos|
(rdb:1) s
D:/Ruby/lib/ruby/site_ruby/1.8/dbi/sql/preparedstatement.rb:73:
@result.join("")
(rdb:1) s
D:/Ruby/lib/ruby/site_ruby/1.8/dbd/mysql/statement.rb:34:
@mutex.synchronize {
(rdb:1) s
D:/Ruby/lib/ruby/site_ruby/1.8/dbd/mysql/statement.rb:35:
@handle.query_with_result = true
(rdb:1) s
D:/Ruby/lib/ruby/site_ruby/1.8/dbd/mysql/statement.rb:36:
@res_handle = @handle.query(sql)
(rdb:1) s
D:/Ruby/lib/ruby/site_ruby/1.8/dbd/mysql/statement.rb:37:
@column_info = self.column_info
(rdb:1) s
D:/Ruby/lib/ruby/site_ruby/1.8/dbd/mysql/statement.rb:119:
retval = []
(rdb:1) s
D:/Ruby/lib/ruby/site_ruby/1.8/dbd/mysql/statement.rb:121:
return [] if @res_handle.nil?
(rdb:1) s
D:/Ruby/lib/ruby/site_ruby/1.8/dbd/mysql/statement.rb:121:
return [] if @res_handle.nil?
(rdb:1) s
D:/Ruby/lib/ruby/site_ruby/1.8/dbd/mysql/statement.rb:123:
unique_key_flag = MysqlField.const_get

(:UNIQUE_KEY_FLAG)
(rdb:1) s
D:/Ruby/lib/ruby/site_ruby/1.8/dbd/mysql/statement.rb:124:
multiple_key_flag = MysqlField.const_get

(:MULTIPLE_KEY_FLAG)

(rdb:1) s
D:/Ruby/lib/ruby/site_ruby/1.8/dbd/mysql/statement.rb:125:
indexed = (unique_key_flag | multiple_key_flag)
(rdb:1) s
D:/Ruby/lib/ruby/site_ruby/1.8/dbd/mysql/statement.rb:125:
indexed = (unique_key_flag | multiple_key_flag)
(rdb:1) s
D:/Ruby/lib/ruby/site_ruby/1.8/dbd/mysql/statement.rb:130:
@res_handle.fetch_fields.each {|col|
(rdb:1) s
D:/Ruby/lib/ruby/site_ruby/1.8/dbd/mysql/statement.rb:130: [BUG]
Segmentation fault
ruby 1.8.7 (2010-01-10 patchlevel 249) [i386-mswin32]


This application has requested the Runtime to terminate it in an unusual
way.
Please contact the application's support team for more information.

D:\Apache2.2\htdocs\ruby_prg\em_ruby\em_db>


statement.rb:130:の@res_handle.fetch_fields.each {|col|で、
Segmentation Faultが生じています。
どうすれば解決できるか、ご指導のほど、お願いします。

別の手法（とみたさんのmysqlを使用した場合）のサンプルコードでは、
問題なく、データが取れています。

#!D:/Ruby/bin/ruby.exe
#
#MySQLへのアクセスサンプルプログラム
# 2009/05/19 CODED BY E.MAEKAWA
#
#
################################################


require "mysql" #MySQLライブラリ
require "rubygems"

mydb = Mysql.new('サーバ名','ユーザ名','パスワード','ＤＢ名')
puts 'mydbの結果は'+ mydb.to_s
#接続確認
res = mydb.query('SELECT * from aplist')
puts 'mydb.queryの結果は'+ res.to_s
#結果確認
puts '【データダンプ】'
res.each do |row|
  #puts row[0].to_s
  puts row.to_s
  puts row.length
end
#テーブル名　取得
res = mydb.list_tables() #テーブル名を返す

puts res.length #テーブル名の数（返されたデータ数）
puts res #list_tablesの結果（テーブル名 arcd 等)
puts '【each doの出力】'
res.each do |name| #テーブル名の格納　res→nemeへ
  puts name
end
puts '【flattenの出力】'
resData = res.flatten #res を一次元の配列にする。
puts resData

puts 'テーブルの数'
puts resData.length # 一次元配列になったデータの数
puts 'テーブル名一覧'
puts res.to_s
#=begin
res.each do |row|
  #puts row[0].to_s
  puts row.to_s
  puts row.length
end

了

冗長ではありますが、ご指導のほど、よろしくお願いします。



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