PHP. Руководство по PHP. 2005

PDOStatement::fetch

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PDOStatement::fetch

(no version information, might be only in CVS)PDOStatement::fetch -- Fetches the next row from a result set

Описание

mixed PDOStatement::fetch ([int fetch_style [, int cursor_orientation [, int cursor_offset]]])

Внимание

-Эта функция является ЭКСПЕРИМЕНТАЛЬНОЙ.

Поведение этой функции, ее имя и относящаяся к ней документация

могут измениться в последующих версиях PHP без уведомления.

Используйте эту функцию на свой страх и риск.

Fetches a row from a result set associated with a PDOStatement object.

Список параметров

fetch_style

Controls how the next row will be returned to the caller. This value must be one of the PDO_FETCH_* constants, defaulting to PDO_FETCH_BOTH.

PDO_FETCH_ASSOC: returns an array indexed by column name as returned in your result set

PDO_FETCH_BOTH (default): returns an array indexed by both column name and column number as returned in your result set

PDO_FETCH_BOUND: returns TRUE and assigns the values of the columns in your result set to the PHP variables to which they were bound with the PDOStatement::bindParam() method

PDO_FETCH_LAZY: combines PDO_FETCH_BOTH and PDO_FETCH_OBJ, creating the object variable names as they are accessed

PDO_FETCH_OBJ: returns an anonymous object with property names that correspond to the column names returned in your result set

PDO_FETCH_NUM: returns an array indexed by column number as returned in your result set, starting at column 0

cursor_orientation

For a PDOStatement object representing a scrollable cursor, this value determines which row will be returned to the caller. This value must be one of the PDO_FETCH_ORI_* constants, defaulting to PDO_FETCH_ORI_NEXT.

offset

For a PDOStatement object representing a scrollable cursor for which the cursor_orientation parameter is set to PDO_FETCH_ORI_ABS, this value specifies the absolute number of the row in the result set that shall be fetched.

For a PDOStatement object representing a scrollable cursor for which the cursor_orientation parameter is set to PDO_FETCH_ORI_REL, this value specifies the row to fetch relative to the cursor position before PDOStatement::fetch() was called.

Примеры

Пример 1. Fetching rows using different fetch styles


<?
$sth = $dbh->prepare("SELECT name, colour FROM fruit");
$sth->execute();
/*Exercise PDOStatement::fetch styles*/
print("PDO_FETCH_ASSOC: ");
print("Return next row as an array indexed by column name\n");
$result = $sth->fetch(PDO_FETCH_ASSOC);
print_r($result);
print("\n");
print("PDO_FETCH_BOTH: ");
print("Return next row as an array indexed by both column name and number\n");
$result = $sth->fetch(PDO_FETCH_BOTH);
print_r($result);
print("\n");
print("PDO_FETCH_LAZY: ");
print("Return next row as an anonymous object with column names as properties\n");
$result = $sth->fetch(PDO_FETCH_LAZY);
print_r($result);
print("\n");
print("PDO_FETCH_OBJ: ");
print("Return next row as an anonymous object with column names as properties\n");
$result = $sth->fetch(PDO_FETCH_OBJ);
print $result->NAME;
print("\n");

?>

Результат выполнения данного примера:

PDO_FETCH_ASSOC: Return next row as an array indexed by column name
Array
([NAME] => apple [COLOUR] => red
)
PDO_FETCH_BOTH: Return next row as an array indexed by both column name and number
Array
([NAME] => banana [0] => banana [COLOUR] => yellow [1] => yellow
)
PDO_FETCH_LAZY: Return next row as an anonymous object with column names as properties
PDORow Object
([NAME] => orange [COLOUR] => orange
)
PDO_FETCH_OBJ: Return next row as an anonymous object with column names as properties
kiwi

Пример 2. Fetching rows with a scrollable cursor


<?
function readDataForwards($dbh){
$sql = 'SELECT hand, won, bet FROM mynumbers ORDER BY BET';
try {
$stmt = $dbh->prepare($sql, array(PDO_ATTR_CURSOR, PDO_CURSOR_SCROLL));
$stmt->execute();
while ($row = $stmt->fetch(PDO_FETCH_NUM, PDO_FETCH_ORI_NEXT)){
$data = $row[0] . "\t" . $row[1] . "\t" . $row[2] . "\n";
print $data;
}
$stmt = null;
}
catch (PDOException $e){
print $e->getMessage();
}}
function readDataBackwards($dbh){
$sql = 'SELECT hand, won, bet FROM mynumbers ORDER BY bet';
try {
$stmt = $dbh->prepare($sql, array(PDO_ATTR_CURSOR, PDO_CURSOR_SCROLL));
$stmt->execute();
$row = $stmt->fetch(PDO_FETCH_NUM, PDO_FETCH_ORI_LAST);
do {
$data = $row[0] . "\t" . $row[1] . "\t" . $row[2] . "\n";
print $data;
} while ($row = $stmt->fetch(PDO_FETCH_NUM, PDO_FETCH_ORI_PRIOR));
$stmt = null;
}
catch (PDOException $e){
print $e->getMessage();
}}
print "Reading forwards:\n";
readDataForwards($conn);
print "Reading backwards:\n";
readDataBackwards($conn);