How could I view results from db in HTML page?

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03-28-2003, 04:41 AM
kkeyan

How could I view results from db in HTML page?

Hi all,

I am querying the Mysql database with cgi-perl and want the output to be displayed in an HTML page? I am able to view the result but with the tags on when I compile. But I need to view the results in a browser. What should I do?

What are the prerequisites if any, I need to take care of?

Sorry if the question sounds stupid.
Would someone help me with a solution?

Thanks in advance.
Karthikeyan:confused:
03-28-2003, 07:10 AM
nicc777

Hi - I am assuming you mean using Perl scripts in your cgi-bin directory and not mod_perl for Apache.

I also assume you are getting the MySQL data.

If I understand your problem correctly you just need to print out the response header in your CGI script. Before printing the HTML, add the following line:

print "Content-type: text/html\n\n";

I hope that was your problem.

Cheers
03-29-2003, 02:25 AM
kkeyan

Re: Query results in webpage:revisited

Hi nicc77,

I have the code sample_db.cgi in cgi-bin/ which is setup as ScriptAlias.

When I give the path of the program in a web-browser,it shows the program as a junk.When I tried compiling at the location, it displays the results just in between the mentioned tags. The program is only ordinary perl and not mod_perl.

Probably, this is because I am new to cgi-programming. Pls help me with some references for cgi-perl programming on the web.

With best regards.
Karthikeyan
03-29-2003, 03:24 AM
kkeyan

Hi nicc77,

It worked. I gave /usr/bin/perl -w for the script beginning. But I have a feeling it should work otherwise too.

It showed Internal Server error 500: What could be the reason? Any idea.

Meanwhile, could I come know of your name plz.

Regards
Karthikeyan
03-29-2003, 09:07 AM
nicc777

Here is a sample Perl script. Call it printenv.pl:

Quote:

#!/usr/bin/perl
##
## printenv -- demo CGI program which just prints its environment
##

print "Content-type: text/html\n\n";
print "<html><body>";
foreach $var (sort(keys(%ENV))) {
$val = $ENV{$var};
$val =~ s|\n|\\n|g;
$val =~ s|"|\\"|g;
print "${var}=\"${val}\" \n";
}
print "</body></html>";

After you have save it in /var/www/cgi-bin ( or wherever your ScriptAlias points to ) do the following ( as root ):

Quote:

# cd /var/www
# chown -Rv apache.apache cgi-bin
# chmod -Rv 770 cgi-bin
# cd /var/www/cgi-bin

Your printenv script should already have the permissions rwxrwx--- if you do a ls -l

Check from the command line:

Quote:

# ./printenv
Content-type: text/html

<html><body>BROWSER="/usr/bin/mozilla" 
COLORFGBG="default;default;0" 
COLORTERM="rxvt-xpm" 
DISPLAY=":0.0" 
ENV="/root/.bashrc" 
GDK_USE_XFT="1" 
GDMSESSION="WindowMaker" 
G_BROKEN_FILENAMES="1" 
etc...

And now try it in your browser: http://127.0.0.1/cgi-bin/printenv

If you get errors, check your error log:

Quote:

# tail -10 /var/log/httpd/error_log

If it says something like "premature end of ..." then there is probably a syntax error in your code that the -w option didn't pick up when you run the app. Probable candidates are:

* Incorrect SQL syntax
* DBI syntax errors ( calling fetcrow_array instead of fetchrow_array - 'h' is missing in the first one )

Debugging can be painfull. What I do if I run into similar problems is to comment everything out that has to do with the SQL query. The SQL query is ussually in a variable $sql, and I then do a:

Quote:

print "SQL=$sql\n";

After I get the output in the Browser, I run it in MySQL command line client, and make sure the output as is expected.

Hope this could help somewhat. In terms of resources, I strongly recommend the following resources:

* www.cgi101.com
* Google

Cheers

PS: my name is simply Nico.