Displaying Query Results as Paragraph Text

2017-11-03 09:05:05

17.2.1 Problem

You want to display a query result as free text.

17.2.2 Solution

Display it with no surrounding HTML structure other than paragraph tags.

17.2.3 Discussion

Paragraphs are useful for displaying free text with no particular structure. In this case all you need to do is retrieve the text to be displayed, encode it to convert special characters to the corresponding HTML entities, and wrap each paragraph within

and

tags. The following examples show how to produce a paragraph for a status display that includes the current date and time, the server version, the client username, and the current database name (if any). These values are available from the following query:

In Perl, the CGI.pm module provides a p( ) function that adds paragraph tags around the string you pass to it. p( ) does not HTML-encode its argument, so you should take care of that by calling escapeHTML( ):

($now, $version, $user, $db) = $dbh->selectrow_array ("SELECT NOW( ), VERSION( ), USER( ), DATABASE( )"); $db = "NONE" unless defined ($db); $para = <

In PHP, you can print the

and

tags around the encoded paragraph text:

$query = "SELECT NOW( ), VERSION( ), USER( ), DATABASE( )"; $result_id = mysql_query ($query, $conn_id); if ($result_id) { list ($now, $version, $user, $db) = mysql_fetch_row ($result_id); mysql_free_result ($result_id); if (!isset ($db)) $db = "NONE"; $para = "Local time on the MySQL server is $now." . " The server version is $version." . " The current user is $user." . " The current database is $db."; print ("

" . htmlspecialchars ($para) . "

"); }

Or, after fetching the query result, you can print the paragraph by beginning in HTML mode and switching between modes:

Local time on the MySQL server is . The server version is . The current user is . The current database is .

To display a paragraph in Python, do something like this::

cursor = conn.cursor ( ) cursor.execute ("SELECT NOW( ), VERSION( ), USER( ), DATABASE( )") row = cursor.fetchone ( ) if row is not None: if row[3] is None: # check database name row[3] = "NONE" para = ("Local time on the MySQL server is %s." + " The server version is %s." + " The current user is %s." + " The current database is %s.") % (row) print "

" + cgi.escape (para, 1) + "

" cursor.close ( )

In JSP, the display might be produced as follows:

SELECT NOW( ), VERSION( ), USER( ), DATABASE( )

Local time on the server is . The server version is . The current user is . The current database is .

The JSP script uses rowsByIndex so that the result set row's columns can be accessed by numeric index.

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