pg_select
(PHP 4 >= 4.3.0, PHP 5)
pg_select — Select records
Описание
pg_select() selects records specified by assoc_array which has field=>value. For a successful query, it returns an array containing all records and fields that match the condition specified by assoc_array.
If options is specified, pg_convert() is applied to assoc_array with the specified flags.
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.
Список параметров
- connection
-
PostgreSQL database connection resource.
- table_name
-
Name of the table from which to select rows.
- assoc_array
-
An array whose keys are field names in the table table_name , and whose values are the conditions that a row must meet to be retrieved.
- options
-
Any number of PGSQL_CONV_FORCE_NULL, PGSQL_DML_NO_CONV, PGSQL_DML_EXEC, PGSQL_DML_ASYNC or PGSQL_DML_STRING combined. If PGSQL_DML_STRING is part of the options then query string is returned.
Возвращаемые значения
Возвращает TRUE в случае успешного завершения или FALSE в случае возникновения ошибки. Returns string if PGSQL_DML_STRING is passed via options .
Примеры
Пример #1 pg_select() example
<?php
$db = pg_connect('dbname=foo');
// This is safe, since $_POST is converted automatically
$rec = pg_select($db, 'post_log', $_POST);
if ($rec) {
echo "Records selected\n";
var_dump($rec);
} else {
echo "User must have sent wrong inputs\n";
}
?>
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Коментарии
Valid options are PGSQL_DML_NO_CONV, PGSQL_DML_EXEC, PGSQL_DMP_ASYNC, PGSQL_DML_STRING (pulled out of source code).
This function does not support selecting from multiple tables. You can get around this by setting the PGSQL_DML_NO_CONV option. This prevents the error which occurs when the function tries to convert the condition array.
I think it is also important to point out that the table_name field is not safe, particularily with the PGSQL_DML_NO_CONV option.
The arguements array field is compulsory, as documented. What isn't so clear is that the array has to actually have some values in it, you can't do a select all.
In summary, this function is good for a very small subset of basic queries. If you are after anything more complex you are better off with pg_query.
David mentioned that you can't do a Select all.However, when executing this script:
<?php
$conn_string = "dbname=mydb";
$db = pg_connect($conn_string);
$selectfields = array("imgid" => "");
$records = pg_select($db,"mmsfiles",$selectfields);
print_r($records);
?>
...I get this result:
Array
(
[0] => Array
(
[imgid] => 1
[file] => /home/wietse/public_html/mms/images/1.gif
[thumb] =>
)
[1] => Array
(
[imgid] => 2
[file] => /home/wietse/public_html/mms/images/2.gif
[thumb] =>
)
[2] => Array
(
[imgid] => 3
[file] => /home/wietse/public_html/mms/images/3.gif
[thumb] =>
)
[3] => Array
(
[imgid] => 4
[file] => /home/wietse/public_html/mms/images/4.gif
[thumb] =>
)
)