#342693 by Damien Tournoud: DatabaseStatementPrefetch should emulate forward only cursor, not a scroll one. From: Damien Tournoud --- includes/database/prefetch.inc | 92 +++++++++++++++++---------------- includes/database/sqlite/database.inc | 10 ++-- 2 files changed, 52 insertions(+), 50 deletions(-) diff --git includes/database/prefetch.inc includes/database/prefetch.inc index d47bf8f..dd62e08 100644 --- includes/database/prefetch.inc +++ includes/database/prefetch.inc @@ -53,11 +53,18 @@ class DatabaseStatementPrefetch implements Iterator, DatabaseStatementInterface protected $data = array(); /** - * Flag indicating whether $data contains valid data. + * The current row, retrieved in PDO::FETCH_ASSOC format. * - * @var bool + * @var Array */ - protected $isValid = FALSE; + protected $currentRow = NULL; + + /** + * The key of the current row. + * + * @var int + */ + protected $currentKey = NULL; /** * The list of column names in this result set. @@ -177,11 +184,9 @@ class DatabaseStatementPrefetch implements Iterator, DatabaseStatementInterface if ($this->resultRowCount) { $this->columnNames = array_keys($this->data[0]); - $this->isValid = TRUE; } else { $this->columnNames = array(); - $this->isValid = FALSE; } if (!empty($logger)) { @@ -189,9 +194,8 @@ class DatabaseStatementPrefetch implements Iterator, DatabaseStatementInterface $logger->log($this, $args, $query_end - $query_start); } - // We will iterate this array so we need to make sure the array pointer is - // at the beginning. - reset($this->data); + // Initialize the first row in $this->currentRow. + $this->next(); return $return; } @@ -267,22 +271,21 @@ class DatabaseStatementPrefetch implements Iterator, DatabaseStatementInterface * The current row formatted as requested. */ public function current() { - $row = current($this->data); - if ($row !== FALSE) { + if (isset($this->currentRow)) { switch ($this->fetchStyle) { case PDO::FETCH_ASSOC: - return $row; + return $this->currentRow; case PDO::FETCH_BOTH: - return $row + array_values($row); + return $this->currentRow + array_values($this->currentRow); case PDO::FETCH_NUM: - return array_values($row); + return array_values($this->currentRow); case PDO::FETCH_LAZY: // We do not do lazy as everything is fetched already. Fallback to // PDO::FETCH_OBJ. case PDO::FETCH_OBJ: - return (object) $row; + return (object) $this->currentRow; case PDO::FETCH_CLASS | PDO::FETCH_CLASSTYPE: - $class_name = array_unshift($row); + $class_name = array_unshift($this->currentRow); // Deliberate no break. case PDO::FETCH_CLASS: if (!isset($class_name)) { @@ -295,18 +298,18 @@ class DatabaseStatementPrefetch implements Iterator, DatabaseStatementInterface else { $result = new $class_name(); } - foreach ($row as $k => $v) { + foreach ($this->currentRow as $k => $v) { $result->$k = $v; } return $result; case PDO::FETCH_INTO: - foreach ($row as $k => $v) { + foreach ($this->currentRow as $k => $v) { $this->fetchOptions['object']->$k = $v; } return $this->fetchOptions['object']; case PDO::FETCH_COLUMN: if (isset($this->columnNames[$this->fetchOptions['column']])) { - return $row[$k][$this->columnNames[$this->fetchOptions['column']]]; + return $this->currentRow[$k][$this->columnNames[$this->fetchOptions['column']]]; } else { return; @@ -318,26 +321,26 @@ class DatabaseStatementPrefetch implements Iterator, DatabaseStatementInterface /* Implementations of Iterator. */ public function key() { - return key($this->data); + return $this->currentKey; } public function rewind() { - reset($this->data); - if (count($this->data)) { - $this->isValid = TRUE; - } + // Nothing to do: our DatabaseStatement can't be rewinded. } public function next() { - // We fetch rows as PDO::FETCH_ASSOC in execute(), - // so no element of the array can ever be FALSE. - if (next($this->data) === FALSE) { - $this->isValid = FALSE; + if (!empty($this->data)) { + $this->currentRow = reset($this->data); + $this->currentKey = key($this->data); + unset($this->data[$this->currentKey]); + } + else { + $this->currentRow = NULL; } } public function valid() { - return $this->isValid; + return isset($this->currentRow); } /* Implementations of DatabaseStatementInterface. */ @@ -347,7 +350,7 @@ class DatabaseStatementPrefetch implements Iterator, DatabaseStatementInterface } public function fetch($fetch_style = NULL, $cursor_orientation = PDO::FETCH_ORI_NEXT, $cursor_offset = NULL) { - if ($this->isValid) { + if (isset($this->currentRow)) { // Set the fetch parameter. $this->fetchStyle = isset($fetch_style) ? $fetch_style : $this->defaultFetchStyle; $this->fetchOptions = $this->defaultFetchOptions; @@ -368,10 +371,9 @@ class DatabaseStatementPrefetch implements Iterator, DatabaseStatementInterface } public function fetchField($index = 0) { - if ($this->isValid && isset($this->columnNames[$index])) { + if (isset($this->currentRow) && isset($this->columnNames[$index])) { // We grab the value directly from $this->data, and format it. - $current = current($this->data); - $return = $current[$this->columnNames[$index]]; + $return = $this->currentRow[$this->columnNames[$index]]; $this->next(); return $return; } @@ -381,10 +383,10 @@ class DatabaseStatementPrefetch implements Iterator, DatabaseStatementInterface } public function fetchObject($class_name = NULL, $constructor_args = array()) { - if ($this->isValid) { + if (isset($this->currentRow)) { if (!isset($class_name)) { // Directly cast to an object to avoid a function call. - $result = (object) current($this->data); + $result = (object) $this->currentRow; } else { $this->fetchStyle = PDO::FETCH_CLASS; @@ -406,8 +408,8 @@ class DatabaseStatementPrefetch implements Iterator, DatabaseStatementInterface } public function fetchAssoc() { - if ($this->isValid) { - $result = current($this->data); + if (isset($this->currentRow)) { + $result = $this->currentRow; $this->next(); return $result; } @@ -428,7 +430,7 @@ class DatabaseStatementPrefetch implements Iterator, DatabaseStatementInterface $result = array(); // Traverse the array as PHP would have done. - while ($this->isValid) { + while (isset($this->currentRow)) { // Grab the row in the format specified above. $result[] = $this->current(); $this->next(); @@ -445,9 +447,8 @@ class DatabaseStatementPrefetch implements Iterator, DatabaseStatementInterface $column = $this->columnNames[$index]; $result = array(); // Traverse the array as PHP would have done. - while ($this->isValid) { - $current = current($this->data); - $result[] = $current[$this->columnNames[$index]]; + while (isset($this->currentRow)) { + $result[] = $this->currentRow[$this->columnNames[$index]]; $this->next(); } return $result; @@ -466,9 +467,8 @@ class DatabaseStatementPrefetch implements Iterator, DatabaseStatementInterface $result = array(); // Traverse the array as PHP would have done. - while ($this->isValid) { - $row = current($this->data); - $result[$row[$key]] = $row[$value]; + while (isset($this->currentRow)) { + $result[$this->currentRow[$key]] = $this->currentRow[$value]; $this->next(); } return $result; @@ -480,12 +480,12 @@ class DatabaseStatementPrefetch implements Iterator, DatabaseStatementInterface $result = array(); // Traverse the array as PHP would have done. - while ($this->isValid) { + while (isset($this->currentRow)) { // Grab the row in its raw PDO::FETCH_ASSOC format. - $row = current($this->data); + $row = $this->currentRow; // Grab the row in the format specified above. $result_row = $this->current(); - $result[$row[$key]] = $result_row; + $result[$this->currentRow[$key]] = $result_row; $this->next(); } diff --git includes/database/sqlite/database.inc includes/database/sqlite/database.inc index 01cfbf7..645b49e 100644 --- includes/database/sqlite/database.inc +++ includes/database/sqlite/database.inc @@ -242,18 +242,20 @@ class DatabaseStatement_sqlite extends DatabaseStatementPrefetch implements Iter } } if ($rename_columns) { + // Put the first row back into the array. + if (isset($this->currentRow)) { + $this->data[0] = $this->currentRow; + } foreach ($this->data as $k => $row) { foreach ($rename_columns as $old_column => $new_column) { $this->data[$k][$new_column] = $this->data[$k][$old_column]; unset($this->data[$k][$old_column]); } } + // Get the first row back into $this->currentRow. + $this->next(); } - // We will iterate this array so we need to make sure the array pointer is - // at the beginning. - reset($this->data); - return $return; }