// How to split the result into pages, like 'limits' in MySQL? // =========================================================== // Tutorial by Neil Craig (neilc@netactive.co.za) // Date: 2001-06-05 // With this example, I will explain paging of database queries where the // result is more than the developer want to PRint to the page, but wish to // split the result into seperate pages. // The table "SAMPLE_TABLE" accessed in this tutorial has 4 fields: // PK_ID, FIELD1, FIELD2 and FIELD3. The types don't matter but you should // define a primary key on the PK_ID field.
$display_rows = 5; // The rows that should be display at a time. You can // modify this if you like.
// Connect to the Oracle database putenv("ORACLE_SID=purk"); putenv("ORACLE_HOME=/export/oracle8i"); putenv("TNS_ADMIN=$ORACLE_HOME/network/admin"); $OracleDBConn = OCILogon("purk","purk","lengana.world");
// This query counts the records $sql_count = "SELECT COUNT(*) FROM SAMPLE_TABLE";
// Parse the SQL string & execute it $row_count=OCIParse($OracleDBConn, $sql_count); OCIExecute($row_count);
// From the parsed & executed query, we get the amount of records found. // I'm not storing this result into a session variable because it allows for // new records to be shown as it is entered by another user while the result // is printed. if (OCIFetch($row_count)) { $num_rows = OCIResult($row_count,1); } else { $num_rows = 0; // If no record was found }
// Free the resources that were used for this query OCIFreeStatement($row_count);
// We need to prepare the query that will print the results as a page. I will // explain the query to you in detail.
// If no page was specified in the url (ex. http://mysite.com/result.php?page=2), // set it to page 1. if (empty($page) || $page == 0) { $page = 1; }
// The start range from where the results should be printed $start_range = (($page - 1) * $display_rows) + 1;
// The end range to where the results should be printed $end_range = $page * $display_rows;
// The main query. It consists of 3 "SELECT" statements nested into each // other. The center query is the query you would normally use to return the // records you want. Do you ordering and "WHERE" clauses in this statement. // We select the rows to limit our results but because the row numbers are // assigned to the rows before any ordering is done, lets the code print the // result unsorted. // The second nested "SELECTED" assigns the new row numbers to the result // for us to select from.
$sql = "SELECT PK_ID, FIELD1, FIELD2, FIELD3, ROW_NO FROM (SELECT PK_ID, "; $sql .= "FIELD1, FIELD2, FIELD3, ROWNUM ROW_NO FROM (SELECT PK_ID, FIELD1, "; $sql .= "FIELD2, FIELD3 FROM SAMPLE_TABLE ORDER BY FIELD3)) WHERE ROW_NO BETWEEN "; $sql .= $start_range." AND ".$end_range;
// Print a message stating that no records was found echo "<tr><td align=center>Sorry! No records was found</td></tr>"; }
// Close the table echo "</TABLE>";
// free resources and close connection OCIFreeStatement($rs); OCILogoff($OracleDBConn);
?> <div align=center> <?php
// Here we will print the links to the other pages
// Calculating the amount of pages if ($num_rows % $display_rows == 0) { $total_pages = $num_rows / $display_rows; } else { $total_pages = ($num_rows / $display_rows) + 1; settype($total_pages, integer); // Rounding the variable }
// If this is not the first page print a link to the previous page if ($page != 1) { echo "<a href='".$PHP_SELF."?page=".($page - 1)."'>Previous</a>"; }
// Now we can print the links to the other pages for ($i = 1; $i <= $total_pages; $i++) { if ($page == $i){ // Don't print the link to the current page echo " ".$i; } else { //Print the links to the other pages echo " <a href='".$PHP_SELF."?page=".$i."'>".$i."</a>"; } }
// If this is not the last page print a link to the next page if ($page < $total_pages) { echo " <a href='".$PHP_SELF."?page=".($page + 1)."'>Next</a>"; }
?> </div> <?php
// I'm just adding this section to print some of the variables for extra info // and some debugging
