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PDOStatement::fetchAll (no version information, might be only in CVS) PDOStatement::fetchAll --
Returns an array containing all of the result set rows
说明array PDOStatement::fetchAll ( [int fetch_style [, int column_index]] ) 参数
- fetch_style
Controls the contents of the returned array as documented in
PDOStatement::fetch(). Defaults to
PDO_FETCH_BOTH.
To return an array consisting of all values of a single column from
the result set, specify PDO_FETCH_COLUMN.
To fetch only the unique values of a single column from the result set,
bitwise-OR PDO_FETCH_COLUMN with
PDO_FETCH_UNIQUE.
To return an associative array grouped by the values of a specified
column, bitwise-OR PDO_FETCH_COLUMN with
PDO_FETCH_GROUP.
- column_index
Returns the indicated 0-indexed column when the value of
fetch_style is
PDO_FETCH_COLUMN. Defaults to 0.
返回值
PDOStatement::fetchAll() returns an array containing
all of the remaining rows in the result set. The array represents each
row as either an array of column values or an object with properties
corresponding to each column name.
Using this method to fetch large result sets will result in a heavy
demand on system and possibly network resources. Rather than retrieving
all of the data and manipulating it in PHP, consider using the database
server to manipulate the result sets. For example, use the WHERE and
SORT BY clauses in SQL to restrict results before retrieving and
processing them with PHP.
范例
例子 1. Fetch all remaining rows in a result set
<?php $sth = $dbh->prepare("SELECT name, colour FROM fruit"); $sth->execute();
/* Fetch all of the remaining rows in the result set */ print("Fetch all of the remaining rows in the result set:\n"); $result = $sth->fetchAll(); print_r($result); ?>
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上例将输出: Fetch all of the remaining rows in the result set:
Array
(
[0] => Array
(
[NAME] => pear
[0] => pear
[COLOUR] => green
[1] => green
)
[1] => Array
(
[NAME] => watermelon
[0] => watermelon
[COLOUR] => pink
[1] => pink
)
) |
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例子 2. Fetching all values of a single column from a result set
The following example demonstrates how to return all of the values of a
single column from a result set, even though the SQL statement itself
may return multiple columns per row.
<?php $sth = $dbh->prepare("SELECT name, colour FROM fruit"); $sth->execute();
/* Fetch all of the values of the first column */ $result = $sth->fetchAll(PDO_FETCH_COLUMN, 0); var_dump($result); ?>
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上例将输出: Array(3)
(
[0] =>
string(5) => apple
[1] =>
string(4) => pear
[2] =>
string(10) => watermelon
) |
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例子 3. Grouping all values by a single column
The following example demonstrates how to return an associative array
grouped by the values of the specified column in the result set. The
array contains three keys: values apple and
pear are returned as arrays that contain two
different colours, while watermelon is
returned as an array that contains only one colour.
<?php $insert = $dbh->prepare("INSERT INTO fruit(name, colour) VALUES (?, ?)"); $insert->execute('apple', 'green'); $insert->execute('pear', 'yellow');
$sth = $dbh->prepare("SELECT name, colour FROM fruit"); $sth->execute();
/* Group values by the first column */ var_dump($sth->fetchAll(PDO_FETCH_COLUMN|PDO_FETCH_GROUP)); ?>
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上例将输出: array(3) {
["apple"]=>
array(2) {
[0]=>
string(5) "green"
[1]=>
string(3) "red"
}
["pear"]=>
array(2) {
[0]=>
string(5) "green"
[1]=>
string(6) "yellow"
}
["watermelon"]=>
array(1) {
[0]=>
string(5) "green"
}
} |
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参见
PDO::query() | PDOStatement::fetch() | PDOStatement::fetchColumn() | PDOStatement::prepare() | PDOStatement::setFetchMode() |
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