12.3. PHPBy its very nature, W3-mSQL is highly specialized for use with the mSQL database server. If you are using MySQL, or if your needs are not covered by W3-mSQL, there are other HTML preprocessors available that offer database support. PHP, which stands for "PHP: Hypertext Preprocessor," is an application very similar to W3-mSQL in spirit. They are both CGI programs that interpret HTML before sending a final page to the browser. They both have their own built-in scripting language. Moreover, they both have tightly integrated database capabilities. However, PHP extends beyond the range of W3-mSQL by offering compatibility with several database servers, including both MySQL and mSQL. PHP's scripting language is also more extensive, covering more possible applications than W3-mSQL. In short, you should use PHP unless you are definitely wedded to mSQL as a database server, in which case some of W3-mSQL's optimizations may suit you. If you use PHP, the HTML example shown earlier which retrieve information from a shark database would now look as follows: <HTML> <HEAD><TITLE>Shark Search Result</title></head> <BODY> <H1>Here are the sharks that match your search...</h1> <p> <? /* We now start to build the query. When finished, a typical query * will look something like this: * SELECT * FROM SHARK WHERE SPECIES='Isurus Paucus' AND AGE=2 */ $query = "select * from sharks where "; if ($species || $age || $location) { $query += " where "; } if ($species) { $query += "species = '$species'"; } if ($age) { if ($species) { $query += " and "; } $query += "age = $age"; } if ($location) { if ($species || $age) { $query += " and "; } $query += "location = '$location'"; } $result = msql("sharks",$query); if (result == -1) { echo("Error : $phperrmsg\n"); exit(1); } $numresults = msql_numrows($result); > <UL> <! if (! $numresults ); > <H2>No results matched</h2> <! else { while ($i < $numresults) { $id[$i] = msql_result($result,$i,"id"); $species[$i] = msql_result($result,$i,"species"); $age[$i] = msql_result($result,$i,"age"); $loc[$i] = msql_result($result,$i,"location"); echo("<LI>"); printf("<IMG SRC=\"graphics/shark%s.gif\" ALIGN=LEFT>", $id[$i]); echo("<B>Species:</b> $species[$i]<br>"); if ($age[$i] == 1) { $age = "Young"; } else if ($age[$i] == 2) { $age = "Adult"; } else if {$age[$i] == 3) { $age = "Old"; } echo("<B>Age:</b> $age<br>"); echo("<B>Location</b> $location[$i]<br>"); } } > </ul> <A HREF="search.html">Search again</a> </body></html> Copyright © 2001 O'Reilly & Associates. All rights reserved. |
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