平野です。

>「ら」の直後に「'」がつながると、この２文字だけ
>でも発生するというのが、わかりました。

との事で、ちょっと試してみました。
網羅性に欠けると思いますが、勉強がてらにテスト
スクリプトを作って実行した所、こちらの環境では
すべてうまく行くようです。

Windows2000 sp4
MySQL 5.0.16-nt  (sjis)
ADO(MDAC2.7 SP1)
MySQL ODBC 3.51 Driver - 
SQLツール ValueSQL 2.2.3359 β


SELECT version();
version() 
--------- 
5.0.16-nt 

drop table qtest;
create table qtest (no int, fielda text);

INSERT INTO qtest VALUES(10010,'''');
INSERT INTO qtest VALUES(10020,'""');
INSERT INTO qtest VALUES(10030,'"');
INSERT INTO qtest VALUES(10040,'''"');

INSERT INTO qtest VALUES(10050,'ら''');
INSERT INTO qtest VALUES(10060,'ら""');
INSERT INTO qtest VALUES(10070,'ら"');
INSERT INTO qtest VALUES(10080,'ら''ら"');

INSERT INTO qtest VALUES(20010,"'");
INSERT INTO qtest VALUES(20020,"''");
INSERT INTO qtest VALUES(20030,"""");
INSERT INTO qtest VALUES(20030,"""'");

INSERT INTO qtest VALUES(20040,"ら'");
INSERT INTO qtest VALUES(20050,"ら''");
INSERT INTO qtest VALUES(20060,"ら""");
INSERT INTO qtest VALUES(20070,"ら""ら'");

INSERT INTO qtest VALUES(30010,'\'');
INSERT INTO qtest VALUES(30020,'\"');
INSERT INTO qtest VALUES(30030,'\'"');

INSERT INTO qtest VALUES(30040,'ら\'');
INSERT INTO qtest VALUES(30050,'ら\"');
INSERT INTO qtest VALUES(30060,'ら\'ら"');

INSERT INTO qtest VALUES(40010,"\'");
INSERT INTO qtest VALUES(40020,"\"");
INSERT INTO qtest VALUES(40030,"'\"");

INSERT INTO qtest VALUES(40040,"ら\'");
INSERT INTO qtest VALUES(40050,"ら\"");
INSERT INTO qtest VALUES(40060,"ら'ら\"");


INSERT INTO qtest VALUES(50010,'ら''97');
INSERT INTO qtest VALUES(50020,"ら'97");

INSERT INTO qtest VALUES(60010,'ら\'97');
INSERT INTO qtest VALUES(60020,"ら\'97");

INSERT INTO qtest VALUES(70010,'''''ら\'''97');
INSERT INTO qtest VALUES(70020,"''''ら\'''97");

INSERT INTO qtest VALUES(80010,'\'ら\'97');
INSERT INTO qtest VALUES(80020,"\'ら\'97");

INSERT INTO qtest VALUES(90010,'\'ら\'97\'');
INSERT INTO qtest VALUES(90020,"\'ら\'97\'");

INSERT INTO qtest VALUES(11010,'''ら\'97''');
INSERT INTO qtest VALUES(11020,"'ら'97'");

INSERT INTO qtest VALUES(12010,'\'\'ら\'\'97');
INSERT INTO qtest VALUES(12020,"\'\'ら\'\'97");


select * from qtest;
no    fielda      
----- ----------- 
10010 '           
10020 ""          
10030 "           
10040 '"          
10050 ら'         
10060 ら""        
10070 ら"         
10080 ら'ら"      
20010 '           
20020 ''          
20030 "           
20030 "'          
20040 ら'         
20050 ら''        
20060 ら"         
20070 ら"ら'      
30010 '           
30020 "           
30030 '"          
30040 ら'         
30050 ら"         
30060 ら'ら"      
40010 '           
40020 "           
40030 '"          
40040 ら'         
40050 ら"         
40060 ら'ら"      
50010 ら'97       
50020 ら'97       
60010 ら'97       
60020 ら'97       
70010 ''ら''97    
70020 ''''ら'''97 
80010 'ら'97      
80020 'ら'97      
90010 'ら'97'     
90020 'ら'97'     
11010 'ら'97'     
11020 'ら'97'     
12010 ''ら''97    
12020 ''ら''97    

結果:42件 (0ms)


以上です。よろしくお願い致します。
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平野　源
hirano@xxxxxxxxxx

ValueSQL -- For all SQL developers --  
http://gwsrv.valuenet.co.jp/ValueSQL/pukiwiki.php
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