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PDO->query()

(no version information, might be only in CVS)

PDO->query() --  Executes an SQL statement, returning a result set as a PDOStatement object

Descrizione

class PDO {

PDOStatement query ( string statement )

}class PDO {

bool query ( string statement, int PDO::FETCH_COLUMN, int colno )

}class PDO {

bool query ( string statement, int PDO::FETCH_CLASS, string classname, array ctorargs )

}class PDO {

bool query ( string statement, int PDO::FETCH_INTO, object object )

}

PDO->query() executes an SQL statement in a single function call, returning the result set (if any) returned by the statement as a PDOStatement object.

For a query that you need to issue multiple times, you will realize better performance if you prepare a PDOStatement object using PDO->prepare() and issue the statement with multiple calls to PDOStatement->execute().

If you do not fetch all of the data in a result set before issuing your next call to PDO->query(), your call may fail. Call PDOStatement->closeCursor() to release the database resources associated with the PDOStatement object before issuing your next call to PDO->query().

Nota: Although this function is only documented as having a single parameter, you may pass additional arguments to this function. They will be treated as though you called PDOStatement->setFetchMode() on the resultant statement object.

Elenco dei parametri

statement

The SQL statement to prepare and execute.

Valori restituiti

PDO->query() returns a PDOStatement object.

Esempi

Esempio 1. Demonstrate PDO::query

A nice feature of PDO->query() is that it enables you to iterate over the rowset returned by a successfully executed SELECT statement.

<?php
function getFruit($conn) {
    $sql = 'SELECT name, colour, calories FROM fruit ORDER BY name';
    foreach ($conn->query($sql) as $row) {
        print $row['NAME'] . "\t";
        print $row['COLOUR'] . "\t";
        print $row['CALORIES'] . "\n";
    }
}
?>

Il precedente esempio visualizzerà:

apple   red     150
banana  yellow  250
kiwi    brown   75
lemon   yellow  25
orange  orange  300
pear    green   150
watermelon      pink    90

Vedere anche:

PDO->exec()
PDO->prepare()
PDOStatement->execute()



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PDO->prepare()RisaliPDO->quote()