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pg_fetch_array

(PHP 4, PHP 5, PHP 7, PHP 8)

pg_fetch_array行を配列として取得する

説明

pg_fetch_array(PgSql\Result $result, ?int $row = null, int $mode = PGSQL_BOTH): array|false

pg_fetch_array() は、取得した行(レコード)を 配列で返します。

pg_fetch_array() は拡張版の pg_fetch_row() です。結果配列のフィールド番号に 対応する要素にデータを格納し、それに加えてフィールド名をキーとした 連想配列にも格納します。デフォルトで、両方ともが有効になっています。

注意: この関数は、 NULL フィールドに PHPの null 値を設定します。

pg_fetch_array() は、 pg_fetch_row() に比べてきわめて遅いというわけでは 「ありません」。そして、きわめて簡単に使用できます。

パラメータ

result

pg_query()pg_query_params() や (様々な関数がありますが、特に) pg_execute() が返した PgSql\Result クラスのインスタンス。

row

取得する行番号。最初の行は 0 です。省略したり null を指定したりした場合は、 次の行を取得します。

mode

返される配列のインデックスを制御するオプションの引数です。 mode は定数で、以下の値を取ることができます。: PGSQL_ASSOC, PGSQL_NUM, PGSQL_BOTHPGSQL_NUM を使うと、配列のインデックスを数値にした配列を返します。PGSQL_ASSOC を使うと、連想配列のインデックスを返します。PGSQL_BOTH を指定すると、数値と連想配列のインデックスを両方含めた形で配列を返します。

戻り値

0 から始まる数値添字の配列か連想配列(フィールド名をキーとする)、 あるいはその両方を返します。配列の各要素の値は文字列です。 データベースの NULL 値は、null として返します。

row が結果の行数より大きい場合や、行が存在しない場合、 そしてそれ以外のエラーが発生した場合は false を返します。 SELECT 以外のクエリから結果を取得しようとした場合も、false を返します。

変更履歴

バージョン 説明
8.1.0 result は、PgSql\Result クラスのインスタンスを期待するようになりました。 これより前のバージョンでは、リソース を期待していました。

例1 pg_fetch_array() の例

<?php

$conn
= pg_pconnect("dbname=publisher");
if (!
$conn) {
echo
"An error occurred.\n";
exit;
}

$result = pg_query($conn, "SELECT author, email FROM authors");
if (!
$result) {
echo
"An error occurred.\n";
exit;
}

$arr = pg_fetch_array($result, 0, PGSQL_NUM);
echo
$arr[0] . " <- Row 1 Author\n";
echo
$arr[1] . " <- Row 1 E-mail\n";

// row パラメータはオプションです。result_type を指定
// したい場合は NULL を渡しておきます。pg_fetch_array を続けてコール
// すると、次の行を取得します。
$arr = pg_fetch_array($result, NULL, PGSQL_ASSOC);
echo
$arr["author"] . " <- Row 2 Author\n";
echo
$arr["email"] . " <- Row 2 E-mail\n";

$arr = pg_fetch_array($result);
echo
$arr["author"] . " <- Row 3 Author\n";
echo
$arr[1] . " <- Row 3 E-mail\n";

?>

参考

add a note

User Contributed Notes 12 notes

up
3
mkb at ele dot uri dot edu
23 years ago
The column names if you use PGSQL_ASSOC or PGSQL_BOTH are always in lowercase, no matter what the name is in the database or in the query.
up
3
jesse at sokieserv dot dhs dot org
23 years ago
As of PHP 4.1.0, you can now use code such as the following to iterate through a result set:

$conn = pg_connect("host=localhost dbname=whatever");
$result = pg_exec($conn, "select * from table");
while ($row = pg_fetch_array($result))
{
echo "data: ".$row["data"];
}

Can be a nice little time saver, PHP with MySQL has supported this for a while but I'm glad to see it extended to PostgreSQL...
up
2
gherson at snet dot net
23 years ago
PGSQL_BOTH is the default, meaning your array size will be doubled.
If you specify this field (result type), include no quotes around it or you won't get any data, not even an error.
Here's my wrapper function:
function SQL_fetch_array($result_ndx, $row, $result_type=PGSQL_ASSOC) {
return pg_fetch_array($result_ndx, $row, $result_type);
up
1
gherson at snet dot net
23 years ago
In addition to returning "false if there are no more rows", pg_fetch_array will also trigger an E_WARNING. You can temporarily turn that error reporting level off and suck out all your data like so:

<?php
$errRptLvl
= error_reporting();
error_reporting($errRptLvl & ~(E_WARNING));

list(
$i,$j)=array(0,0);
while (
$selection[$i++] = $this->fetchArray($j++)); // (fetchArray is a pg_fetch_array wrapper.)
error_reporting($errRptLvl); // Restore error reporting level.
unset($selection[$i-1]); // Delete the last, empty row.
return $selection;
?>
up
1
strata_ranger at hotmail dot com
15 years ago
Note that when using PGSQL_BOTH, numerically and associatively indexed fields are separate variables and treated as such:

<?php
$res
= pg_query("Select 'foo' as bar");

$data = pg_fetch_array($res, 0, PGSQL_BOTH);

var_dump($data);
// Array(2)
// {
// [0] => string(3) "foo"
// ["bar"] => string(3) "foo"
// }

// This won't affect $data['bar']
$data[0] = 'bar';

var_dump($data);
// Array(2)
// {
// [0] => string(3) "bar"
// ["bar"] => string(3) "foo"
// }
?>

If you want to have reference binding between your numeric and associative indexes, you'll have to establish that yourself:

<?php

$result
= pg_query("Select 'foo' as bar");

$data = pg_fetch_row($result);

// Establish references between column name/number
$from = $data;
foreach(
$from as $cx => $value)
{
$key = pg_field_name($result, $cx);
if (
is_string($key)) $data[$key] =& $data[$cx];
}

var_dump($data);
// Array(2)
// {
// [0] => &string(3) "foo"
// ["bar"] => &string(3) "foo"
// }
// Note the reference binding between $data[0] and $data['bar']

$data[0] = 'baz';

var_dump($data);
// Array(2)
// {
// [0] => &string(3) "baz"
// ["bar"] => &string(3) "baz"
// }

?>
up
1
akm at e-nterart dot pl
21 years ago
(Timesaver) Be aware of the fact that keys in array returned by this function are (well, at least as of 4.2.3) of the same case as SQL column names (e.g. if your column name is ID then key name is also ID, not id or Id), and the keys in associative array are CASE SENSITIVE!!! So don't be surprised if you get unexpected results. Double check SQL column names and the key names.
up
0
devnull
19 years ago
In response to eth0's comment below about SELECT'ing from two tables where the tables have columns with the same names, you can get around this problem like this:

"SELECT table1.foo AS foo1, table2.foo AS foo2 FROM table1, table2"

In the associative array returned, the keys will be "foo1" and "foo2".
up
-1
anonymous
19 years ago
Hopefully most people realize this on their own, but the examples below where people tried to get creative with getting numerical or associative (not both) keys in the result are rather pointless. See the pg_fetch_assoc() and pg_fetch_row() for the built in functions that do this automatically. It's generally a better idea to use one of these other functions unless you *need* to access fields by both collumn name *and* index.
up
-1
enyo at www.red-link.com
21 years ago
Just because it is not really clear how to specify the result type, I poste this message.

I wrote a wrapper function which looks like this:

<?php
function db_fetch_array ($result, $row = NULL, $result_type = PGSQL_ASSOC)
{
$return = @pg_fetch_array ($result, $row, $result_type);
return
$return;
}
?>

I think this way it is quite comfortable to get the arrays you want.
up
-2
eth0 at fins
23 years ago
Please remember that if you have for example a table Customers with "cust_ID", "name" and "address" and another table Users with "u_ID","name" and "other" and then you SELECT WHERE cust_ID=u_ID then you'll get in the result array ONLY ONE "name" field, precisely the last one resulted from the select!!!
up
-2
elliot at nospam dot rightnowtech dot com
23 years ago
Just remember when you 'or die' to close your table(s) or you may get a confused look from non-internet explorer users.
up
-3
Dave O
19 years ago
I found this out through help from the mailing lists. If you need to reset the internal counter, use the pg_result_seek, similar to:

pg_result_seek($result, 0)

...plagiarized from the comment on the function's doc page.