Archive:PHP and MySQL Programming/Database Connectivity: Difference between revisions

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 == Retrieving data from a SELECT Query ==
+There are many methods for retrieving data from a SELECT Query.
+If we take, for example, the following code :
+ <?
+ # --- Connect To Database ---
+ $db = "db1";
+ $link = mysql_connect("localhost", "user", "pass");
+ mysql_select_db($db, $link);
+ # --- Select Info from Database ---
+ $result = mysql_query ("SELECT val1, val2 FROM tbl1");
+ ?>
+To now retrieve the data from the $result variable, we can use one of many methods. The recommended method, however, is to sequentially go through each row of the table, storing it into a one-dimensional array. We do this by using the mysql_fetch_row() function, passing it the variable intowhich the result is stored. Here is a simple example :
+ <?
+ while ($row = mysql_fetch_row($result)){
+    foreach ($row as $field) {
+       print "$filed . ";
+    }
+    print "<BR>";
+ }
+ ?>
+This will simply output the result in table-like format.
+Here is another example of using this method :
+ <?
+ $counter = 0;
+ while ($row = mysql_fetch_row($result)){
+    $val1[$counter] = $row[0];
+    $val2[$counter] = $row[1];
+    $counter++;
+ }
+ $numRows = $counter;
+ ?>
+The above example, simply splits the results up into multiple one-dimensional arrays, for easy manipulation.
 == Closing a Database Connection ==