mirror of
https://github.com/silverstripe/silverstripe-framework
synced 2024-08-22 10:35:53 +02:00
253 lines
4.9 KiB
PHP
253 lines
4.9 KiB
PHP
<?php
|
|
|
|
/**
|
|
* Abstract query-result class.
|
|
*
|
|
* Once again, this should be subclassed by an actual database implementation
|
|
* such as {@link MySQLQuery}.
|
|
*
|
|
* It will only ever be constructed by a subclass of {@link SS_Database} and
|
|
* contain the result of a database query as an iteratable object.
|
|
*
|
|
* Primarily, the SS_Query class takes care of the iterator plumbing, letting
|
|
* the subclasses focusing on providing the specific data-access methods that
|
|
* are required: {@link nextRecord()}, {@link numRecords()} and {@link seek()}
|
|
*
|
|
* @package framework
|
|
* @subpackage model
|
|
*/
|
|
abstract class SS_Query implements Iterator {
|
|
|
|
/**
|
|
* The current record in the interator.
|
|
*
|
|
* @var array
|
|
*/
|
|
private $currentRecord = null;
|
|
|
|
/**
|
|
* The number of the current row in the interator.
|
|
*
|
|
* @var int
|
|
*/
|
|
private $rowNum = -1;
|
|
|
|
/**
|
|
* Flag to keep track of whether iteration has begun, to prevent unnecessary
|
|
* seeks.
|
|
*
|
|
* @var boolean
|
|
*/
|
|
private $queryHasBegun = false;
|
|
|
|
/**
|
|
* Return an array containing all the values from a specific column. If no
|
|
* column is set, then the first will be returned.
|
|
*
|
|
* @param string $column
|
|
*
|
|
* @return array
|
|
*/
|
|
public function column($column = null) {
|
|
$result = array();
|
|
|
|
while($record = $this->next()) {
|
|
if($column) {
|
|
$result[] = $record[$column];
|
|
} else {
|
|
$result[] = $record[key($record)];
|
|
}
|
|
}
|
|
|
|
return $result;
|
|
}
|
|
|
|
/**
|
|
* Return an array containing all values in the leftmost column, where the
|
|
* keys are the same as the values.
|
|
*
|
|
* @return array
|
|
*/
|
|
public function keyedColumn() {
|
|
$column = array();
|
|
|
|
foreach($this as $record) {
|
|
$val = $record[key($record)];
|
|
$column[$val] = $val;
|
|
}
|
|
|
|
return $column;
|
|
}
|
|
|
|
/**
|
|
* Return a map from the first column to the second column.
|
|
*
|
|
* @return array
|
|
*/
|
|
public function map() {
|
|
$column = array();
|
|
|
|
foreach($this as $record) {
|
|
$key = reset($record);
|
|
$val = next($record);
|
|
$column[$key] = $val;
|
|
}
|
|
|
|
return $column;
|
|
}
|
|
|
|
/**
|
|
* Returns the next record in the iterator.
|
|
*
|
|
* @return array
|
|
*/
|
|
public function record() {
|
|
return $this->next();
|
|
}
|
|
|
|
/**
|
|
* Returns the first column of the first record.
|
|
*
|
|
* @return string
|
|
*/
|
|
public function value() {
|
|
$record = $this->next();
|
|
|
|
if($record) {
|
|
return $record[key($record)];
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Return an HTML table containing the full result-set.
|
|
*/
|
|
public function table() {
|
|
$first = true;
|
|
$result = "<table>\n";
|
|
|
|
foreach($this as $record) {
|
|
if($first) {
|
|
$result .= "<tr>";
|
|
foreach($record as $k => $v) {
|
|
$result .= "<th>" . Convert::raw2xml($k) . "</th> ";
|
|
}
|
|
$result .= "</tr> \n";
|
|
}
|
|
|
|
$result .= "<tr>";
|
|
foreach($record as $k => $v) {
|
|
$result .= "<td>" . Convert::raw2xml($v) . "</td> ";
|
|
}
|
|
$result .= "</tr> \n";
|
|
|
|
$first = false;
|
|
}
|
|
$result .= "</table>\n";
|
|
|
|
if($first) return "No records found";
|
|
return $result;
|
|
}
|
|
|
|
/**
|
|
* Iterator function implementation. Rewind the iterator to the first item
|
|
* and return it.
|
|
*
|
|
* Makes use of {@link seek()} and {@link numRecords()}, takes care of the
|
|
* plumbing.
|
|
*
|
|
* @return array
|
|
*/
|
|
public function rewind() {
|
|
if($this->queryHasBegun && $this->numRecords() > 0) {
|
|
$this->queryHasBegun = false;
|
|
|
|
return $this->seek(0);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Iterator function implementation. Return the current item of the
|
|
* iterator.
|
|
*
|
|
* @return array
|
|
*/
|
|
public function current() {
|
|
if(!$this->currentRecord) {
|
|
return $this->next();
|
|
} else {
|
|
return $this->currentRecord;
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Iterator function implementation. Return the first item of this iterator.
|
|
* @return array
|
|
*/
|
|
public function first() {
|
|
$this->rewind();
|
|
|
|
return $this->current();
|
|
}
|
|
|
|
/**
|
|
* Iterator function implementation. Return the row number of the current
|
|
* item.
|
|
*
|
|
* @return int
|
|
*/
|
|
public function key() {
|
|
return $this->rowNum;
|
|
}
|
|
|
|
/**
|
|
* Iterator function implementation. Return the next record in the iterator.
|
|
*
|
|
* Makes use of {@link nextRecord()}, takes care of the plumbing.
|
|
*
|
|
* @return array
|
|
*/
|
|
public function next() {
|
|
$this->queryHasBegun = true;
|
|
$this->currentRecord = $this->nextRecord();
|
|
$this->rowNum++;
|
|
return $this->currentRecord;
|
|
}
|
|
|
|
/**
|
|
* Iterator function implementation. Check if the iterator is pointing to a
|
|
* valid item.
|
|
*
|
|
* @return boolean
|
|
*/
|
|
public function valid() {
|
|
if(!$this->queryHasBegun) {
|
|
$this->next();
|
|
}
|
|
|
|
return $this->currentRecord !== false;
|
|
}
|
|
|
|
/**
|
|
* Return the next record in the query result.
|
|
*
|
|
* @return array
|
|
*/
|
|
abstract public function nextRecord();
|
|
|
|
/**
|
|
* Return the total number of items in the query result.
|
|
*
|
|
* @return int
|
|
*/
|
|
abstract public function numRecords();
|
|
|
|
/**
|
|
* Go to a specific row number in the query result and return the record.
|
|
*
|
|
* @param int $rowNum Tow number to go to.
|
|
*
|
|
* @return array
|
|
*/
|
|
abstract public function seek($rowNum);
|
|
}
|