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PDOStatement::fetch (no version information, might be only in CVS) PDOStatement::fetch --
Fetches the next row from a result set
说明mixed PDOStatement::fetch ( [int fetch_style [, int cursor_orientation [, int cursor_offset]]] ) | 警告 | 本函数是实验性的。本函数的行为，包括函数名称以及其它任何关于本函数的文档可能会在没有通知的情况下随
PHP 以后的发布而改变。使用本函数风险自担。 |
Fetches a row from a result set associated with a PDOStatement object.
参数
- 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.
例
例子 1. Fetching rows using different fetch styles
<?php
$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 $result->NAME;
print("\n");
?>
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上例将输出： PDO_FETCH_ASSOC: Return next row as an array indexed by column name
Array
(
[NAME] => apple
[COLOUR] => red
)
PDO_FETCH_BOTH: Return next row as an array indexed by both column name and number
Array
(
[NAME] => banana
[0] => banana
[COLOUR] => yellow
[1] => yellow
)
PDO_FETCH_LAZY: Return next row as an anonymous object with column names as properties
PDORow Object
(
[NAME] => orange
[COLOUR] => orange
)
PDO_FETCH_OBJ: Return next row as an anonymous object with column names as properties
kiwi |
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例子 2. Fetching rows with a scrollable cursor
<?php
function readDataForwards($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);
?>
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上例将输出： Reading forwards:
21 10 5
16 0 5
19 20 10
Reading backwards:
19 20 10
16 0 5
21 10 5 |
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参见
| PDO::query() | | PDOStatement::fetchAll() | | PDOStatement::fetchColumn() | | PDOStatement::prepare() | | PDOStatement::setFetchMode() |
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