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asp.net database connection and database connection
- WBOYOriginal
- 2016-07-29 08:34:46986browse
4. Database connection
The above has introduced asp.net database connection and database connection, including the content of asp.net database connection. I hope it will be helpful to friends who are interested in PHP tutorials.
Through PHP you can easily connect to the database, request data and display it in your web site, and even modify the data in the database. MySQL is a very popular database, and there are many tutorials on PHP and MySQL on the Internet. MySQL is free, which may attract many people. Due to its wide application, I don't want to go into details about the use of MySQL here. Oracle is widely used in enterprise applications, so we will use Oracle to introduce the connection between PHP and database. We will certainly not mention the design principles of the Oracle database, as this is beyond the scope of our discussion.
PHP provides two sets of functions to connect to Oracle, namely ORA_ and OCI functions. The ORA_ function is slightly outdated. The OCI function update is said to be better. The usage syntax of the two is almost the same. As mentioned before, your PHP installation options should support the use of both.
For more knowledge about installing PHP3-enabled Apache server on Microsoft Windows platform and more knowledge about Oracle database, please consult the following URL: www.csoft.net/~vsbabu/articles/oraphp.html.
4.1 Connect
if ($c
{
echo "SUCCESS ! Connected to databasen";
}
else
{
echo "Failed :-( Could not connect to databasen";
}
Ora_Logoff($conn);
phpinfo();
?>
The above code uses the Oracle database name defined by TNSNAME (specified in your tnsnames.ora file), User name and password to connect to the database. On the basis of successful connection, the ora_logon function returns a non-zero connection ID and stores it in the variable $conn.
4.2 Query
Assuming that the connection to the database is ready, let’s start with the actual application. Database query.The following code demonstrates a typical example of connecting and querying:
/*
* Connect to the database and execute the query
*/
function printoraerr($in_cur)
{
// Check if there is an error in Oracle
// If If there is an error, it will be displayed
// When the pointer is activated, this function is called after each request to Oracle
if(ora_errorcode($in_cur))
echo "Oracle code - ".ora_error($in_cur)."n";
return;
}
/**main program*/
if (!($c
{
echo "Connection to database failedn";
exit;
}
echo "Connected as connection - $connn";
echo "Opening cursor ...
n";
$cursor=ora_open($conn); printoraerr($cursor);
echo "Opened cursor - $ cursor
n";
$qry="select user,sysdate from dual";
echo "Parsing the query $qry ...
n" ;
ora_parse($cursor,$qry,0); printoraerr($cursor);
echo "Query parsed
n";
echo "Executing cursor ...
n";
ora_exec($ cursor); printoraerr($cursor);
echo "Executed cursor
n";
echo "Fetching cursor ...
n";
while(ora_fetch($cursor))
{
$user= ora_getcolumn($cursor,0); printoraerr($cursor);
$sysdate=ora_getcolumn($cursor,1); printoraerr($cursor);
echo " row = $user, $sysdate n";
}
echo "Fetched all records
n";
echo "Closing cursor ...
n";
ora_close($cursor);
echo "Closed cursor< br>n";
echo "Logging off from oracle...
n";
ora_logoff($conn);
echo "Logged off from oracle
n";
?>
(translation Note: The above code snippet lacks comments, please refer to the Oracle database function section of the PHP Manual)
4.3 Displaying results
The following code demonstrates how to query the database and output the results:
function printoraerr($in_cur, $conn )
{
// Check if Oracle has an error
// If there is an error, display it
// This function is called after each Oracle request when the pointer is activated
// If it encountered an error, we exit immediately
if(ora_errorcode ($in_cur))
{
echo "Oracle code - ".ora_error($in_cur)."
n";
ora_logoff($conn);
exit;
}
return;
}
function exequery( $w_qry,$conn)
{
$cursor=ora_open($conn); printoraerr($cursor,$conn);
ora_parse($cursor,$w_qry,0); printoraerr($cursor,$conn);
ora_exec ($cursor); printoraerr($cursor,$conn);
$numrows=0;
$w_numcols=ora_numcols($cursor);
// Display header
echo "n"; n";
for ($i=0;$i<$w_numcols;$i++)
{
$align=(ora_columntype( $cursor,$i)=="NUMBER")?"RIGHT":"LEFT";
echo "t".ora_columnname($cursor,$i)."n";
}
echo "
while(ora_fetch($cursor))
{
echo "n"; n";
for ($i=0;$i< $w_numcols;$i++)
{
$align=(ora_columntype($cursor,$i)=="NUMBER")?"RIGHT":"LEFT";
if(ora_columntype($cursor,$i)==" LONG")
echo "".<br>ora_getcolumn($cursor,$i)."
else
echo "".ora_getcolumn($cursor,$i)." n";
printoraerr($cursor,$conn);
}
$numrows++;
echo "
}
if ($numrows==0)
echo "Query returned no records
< /B>
else
{
echo "n"; n";
echo "Count n";
echo "$numrows n";
echo "
}
echo "n";
ora_close($cursor);
return;
}
// Main program
if(!($c
{
echo "Error: Cannot connect to databasen";
exit;
}
$qry="SELECT
deptno "Dept"
,empno "Emp"
,empnm "Name"
,salary "Salary"
FROM
employee
ORDER BY 1,2";
exequery($qry);
ora_logoff ($conn);
?>
(Translator’s Note: The above code segment lacks comments, please refer to the Oracle database function section of the PHP Manual)
4.4 Oracle login based on HTTP
Add the following code before the PHP page code. Confirm Oracle login. Note that you must set $SID correctly.
if(!isset($PHP_AUTH_USER))
{
Header("WWW-authenticate: basic realm="$SID"");
Header("HTTP/1.0 401 Unauthorized");
$title= "Login Instructions";
echo "
n";
You are not authorized to enter the site
exit;
}
else
{
if (!($c
{
Header ("WWW-authenticate: basic realm="$SID"");
Header("HTTP/1.0 401 Unauthorized");
$title="Login Instructions";
echo "
n";
You are not authorized to enter the site
exit;
}
}
?>
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