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Henrik Olsen (Henrik.Olsen@iaeste.dk)
Thu, 27 Nov 1997 18:07:38 +0200 

From: "Henrik Olsen" <Henrik.Olsen@iaeste.dk>
Date:          Thu, 27 Nov 1997 18:07:38 +0200
Subject:       Re: Synchronisation in msql
Message-ID: <4061C3D2AAD@iaeste.dk>

On 26 Nov 97 at 3:02, BJARKE CHRISTESEN wrote:

> Hello
>
> I am a student at advanced computer Studies, and we are using msql in
> a project. Now have to show, how there is taken care of
> synchronisation problems (readers/writers). Since I don't get any
> Answer from Hughes, I guess there may be somebody ou here who has an
> idea about where to get some material.
>
>
> Greetinrgs
> Bjarke Christesen
> d96bc@novell02.sdrborges.dk

Since mSQL is non-threaded, and queues multiple requests, there
aren't really any syncronisation problems.

Henrik Olsen 

--
CNA, working on CNE.    URL="http://www.iaeste.dk/~henrik/"
Rule #1 for keeping your face young and good looking:
 Don't breathe fire when you have a beard.
From grantt@nortel.ca  Thu Nov 27 17:03:51 1997
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Date: 27 Nov 1997 17:00 EST
Sender: "Grant Totten" <grantt@nortel.ca>
To: msql-list@Bunyip.Com
From: "Grant Totten" <grantt@nortel.ca>
Subject: [msql-list] Bad handshake still happening with 2.0.3!

Hi all,

A while ago I posted about getting an error message every once in
a while when connecting to a database.  The message indicated a 'bad
handshake' was happening.  It only seemed to happen when the database
server was fairly busy.

Recently, someone sent me an e-mail indicating they were having this
problem and that going to version 2.0.3 of msql solved it.  So today I
downloaded and installed 2.0.3 on our server.  This afternoon, I did some
testing and discovered that the connect call will still fail every once
in a while with a 'bad handshake' message.  Argh!  

So I had to write a hack like this:

   while ($tries-- > 0) {
      #
      # Attempt to connect to database
      #
      if(!($DBH = Msql->connect($host, $database))) {
         #
         # This means the connect failed.  Set error status
         # and sleep for 2 seconds before trying again.
         #
         $error = 1;
         &main::Debug("Trying...");
         sleep 2;
      } else {
         #
         # The connection was successful.  Skip to the end
         # of the loop.
         #
         $error = 0;
         last;
      }
   } #end while
   
   #
   # Return error status or Database Handle
   #
   if ($error) {
      return (0);
   } else {
      return ($DBH);
   }

Sigh.

Any suggestions?

Thanks.

Grant Totten
Nortel Public Data Networks
grantt@nortel.ca
From wcchu@e3000.kh.misnet.net  Fri Nov 28 04:31:21 1997
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From: Wei-Cheng Chu <wcchu@e3000.kh.misnet.net>
Message-Id: <199711280927.RAA16691@e3000.kh.misnet.net>
Subject: How do I duplicate tables?
To: msql-list@services.bunyip.com
Date: Fri, 28 Nov 1997 17:27:02 +0800 (CST)
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Hi!

Can anyone tell me how to duplicate a new table from an existing one
in the same database in C programs in msql-2.0.3?

I've check msql.h and found that there's a declaration for function
msqlCreateTable(), but it seems not to be described in the manual.
Can I use it? If I can, how should I use it? 

If I can't, I think the only way is to use msqlQuery(). But I don't
want the SQL statement for the table definition fixed in the source
since the definition of the "template table" maybe changed some other
day. So how can I dynamically obtain an existing table's definition and
convert it into a SQL statement for creating new tables?

Thanks in advance.
From ernst@pem.com  Fri Nov 28 09:52:07 1997
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From: "Ernesto Baschny" <ernst@pem.com>
To: Kevin McQuiggin <mcquiggi@sfu.ca>, msql-list@Bunyip.Com
Date: Fri, 28 Nov 1997 15:51:52 +0100
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Subject: Re: Simple Question, Apache and mSQL
Priority: normal
In-reply-to: <3.0.1.32.19971126122452.03095ef8@ferrari.sfu.ca>
X-mailer: Pegasus Mail for Win32 (v2.54)

> Date:          Wed, 26 Nov 1997 15:25:49 -0500 (EST)
> Subject:       Simple Question, Apache and mSQL

> Here's a question that is alluded to in the FAQ, but not specifically
> answered:
> 
> I run Apache as my web server, under FreeBSD. Both are current versions.
> 
> How must I modify my srm.conf file to allow files of type ".msql" to be
> automatically parsed by /usr/local/www/cgi-bin/w3-msql ?
> 
> I gather from an extensive reading of the docs and FAQ that the AddHandler,
> AddType, and Action directives (or some combo) are the way to do this. But
> several combinations, e.g. 
> 
> AddHandler w3-msql .msql
> Action w3-msql /usr/local/www/cgi-bin/w3-msql
> 
> etc. have all proven unsuccessful.

Try not using the full path, just the path beginning from your document
root:

  AddHandler w3-msql .msql
  Action w3-msql /cgi-bin/w3-msql

This works fine for me.

--
Ernesto  <baschneo@trick.informatik.uni-stuttgart.de>
PEM GmbH <ernst@pem.com> 
Stuttgart - Germany
From mario@wright.zmms.tu-berlin.de  Fri Nov 28 10:44:14 1997
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Date: Fri, 28 Nov 1997 16:44:02 +0100
From: Mario Lasch <Mario.Lasch@zmms.tu-berlin.de>
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To: msql-list@services.bunyip.com
Subject: Question about _rowid
Content-Type: multipart/mixed; boundary="------------6FE803DF734C1F4E45E5D350"

--------------6FE803DF734C1F4E45E5D350
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Content-transfer-encoding: 8bit

Question about _rowid:

Using Mini SQL Version 2.0.3 on our system (Linux 2.0.30 i686,
S.u.S.E. 5.0), we have a database X containing two tables X1 and X2.

X1 and X2 are defined as:

        CREATE TABLE X1 (
                a text(10), 
                b int not null
        )\g
        CREATE TABLE X2 (
                a text(10), 
                b int not null
        )\g

with these values:

        INSERT INTO X1 (a,b)
                VALUES ('test1',0)\g
        INSERT INTO X1 (a,b)
                VALUES ('test2',1)\g
        INSERT INTO X2 (a,b)
                VALUES ('test3',0)\g
        INSERT INTO X2 (a,b)
                VALUES ('test4',1)\g

1) using the msql-interface we get an error on every select after this
   select:

        SELECT X1.a, X1.b, X1._rowid, X2.a, X2.b, X2._rowid
                FROM X1, X2
                WHERE X2.b = X1._rowid\g

   the server msql2d crashes with this output:

        Hit by a sig 11
        Forced server shutdown due to bad signal!
        Forcing close on Socket 6
        IOT trap/Abort

2) if we reverse the condition as in this select:

        SELECT X1.a, X1.b, X1._rowid, X2.a, X2.b, X2._rowid
                FROM X1, X2
                WHERE X1._rowid = X2.b\g

   we get this - in our opinion wrong -  output:

        Query OK.  0 row(s) modified or retrieved.

Is this behaviour caused by our misunderstanding of the semantics of
msql or is the reason for this an msql-error?

Can anyone produce the same results?  For your convenience we attached
a shell-script to reproduce this sequence. When you run it, it prompts
you for the name of an already created database where you want to test
this and which case you want to use.

mario

-- 
-----------------------------------------------
Mario Lasch

eMail: Mario.Lasch@zmms.tu-berlin.de
http://www.zmms.tu-berlin.de/~mario

Technische Universität Berlin
Zentrum Mensch-Maschine-Systeme (ZMMS)
Sekr. TIB 4/5-3
Gustav-Meyer-Allee 25
D-13355 Berlin

Tel.: ++49 30 314 72578
Fax : ++49 30 314 72581
http://www.zmms.tu-berlin.de/
-----------------------------------------------

--------------6FE803DF734C1F4E45E5D350
Content-type: application/x-sh; name="script.sh"
Content-transfer-encoding: 7bit
Content-Disposition: inline; filename="script.sh"

#!/bin/sh
if [ "$1" != "" ]; then 
	DB=$1;
else
	echo -n "Which database should be used to run the example? ";
	read DB;
	echo
fi
if relshow $DB | egrep "( X1 | X2 )" > /dev/null; then
	echo "In database $DB you already have table X1 or X2."
	echo "Using this script would drop these tables." 
	echo "Please use another database instead or drop these tables,"
	echo "if you really want this." 
	exit;
fi
CASE=$2
while [ "$CASE" != "1" -a "$CASE" != "2" ]; do
	echo "Case 1: SELECT ... WHERE X2.b = X1._rowid\g"
	echo "Case 2: SELECT ... WHERE X1._rowid = X2.b\g"
	echo -n "Which case should be used? (1,2) ";
	read CASE;
	if [ "$CASE" = "1" -o "$CASE" = "2" ]; then
		break;
	else
		echo
		echo "You have to type 1 or 2";
	fi;
done
if [ "$CASE" = "1" ]; then
	WHERE="WHERE X2.b = X1._rowid\g";
elif [ "$CASE" = "2" ]; then
	WHERE="WHERE X1._rowid = X2.b\g";
fi;
echo
echo "running case $CASE (SELECT ... $WHERE) in database: $DB";
cat <<- eof | msql $DB
	CREATE TABLE X1 (
		a text(10), 
		b int not null
	)\g
	CREATE TABLE X2 (
		a text(10), 
		b int not null
	)\g
	INSERT INTO X1 (a,b)
		VALUES ('test1',0)\g
	INSERT INTO X1 (a,b)
		VALUES ('test2',1)\g
	INSERT INTO X2 (a,b)
		VALUES ('test3',0)\g
	INSERT INTO X2 (a,b)
		VALUES ('test4',1)\g
	SELECT X1.a, X1.b, X1._rowid, X2.a, X2.b, X2._rowid
		FROM X1, X2\g
	SELECT X1.a, X1.b, X1._rowid, X2.a, X2.b, X2._rowid
		FROM X1, X2
		$WHERE
	DROP TABLE X1\g
	DROP TABLE X2\g
eof

--------------6FE803DF734C1F4E45E5D350--
From royolsen@indra.com  Fri Nov 28 12:45:55 1997
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Date: Fri, 28 Nov 1997 10:45:45 -0700
To: msql-list@services.bunyip.com
From: Roy Olsen <royolsen@indra.com>
Subject: Re: a question of msql with Win95
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xiyuan,

Did you solve this problem?  I replied to your second message but
apparently it bounced.  I notice your domain is not always available.  I
noticed that when I ping'ed it sometimes it timed out.  Here is the reply I
sent...

Once you create the "test" subdirectory of "msqldb" the database has been
created.  Just run the msql monitor and use the SQL statement "create
table..." to make tables in the database.

Roy

At 01:37 PM 11/25/97 +0800, you wrote:
>Hi, thanks a lot.
>I just do it as you told me but unluck, I can not create the table and can
>do nothing more. 
>
>--xiyuan
>
>>
>> This is a problem with mSQL 1.0.16 and Win95.  The workaround is simple.
>> Just create a "test" subdirectory in your "msqldb" directory.
>>
>> >Hi, I have setup the msql116.zip on my win95 box and also download the 
>> >php2msql1.exe file. Msqld run ok. But when I enter "msqladm create
test" to 
>> >create a database, there is a error message:
>> >mSQL command fialed!
>> >Server error = Permission denied
>> >
>
>