(PHP 5)
mysqli->field_count — Regresa el número de columnas para la consulta más reciente
Estilo por procedimientos:
Estilo orientado a objetos (método):
Regresa el número de columnas para la más reciente consulta en la conexión representada por el parámetro identificador_de_enlace . Esta función puede ser usada cuando se use la función Returns the number of columns for the most recent query on the connection represented by the link parameter. This function can be useful when using the mysqli_store_result() function to determine if the query should have produced a non-empty result set or not without knowing the nature of the query.
An integer representing the number of fields in a result set
Example#1 Object oriented style
<?php
$mysqli = new mysqli("localhost", "my_user", "my_password", "test");
$mysqli->query( "DROP TABLE IF EXISTS friends");
$mysqli->query( "CREATE TABLE friends (id int, name varchar(20))");
$mysqli->query( "INSERT INTO friends VALUES (1,'Hartmut'), (2, 'Ulf')");
$mysqli->real_query($HTTP_POST_VARS['query']);
if (mysqli_field_count($link)) {
/* this was a select/show or describe query */
$result = $mysqli->store_result();
/* process resultset */
$row = $result->fetch_row();
/* free resultset */
$result->close();
}
/* close connection */
$mysqli->close();
?>
Example#2 Procedural style
<?php
$link = mysqli_connect("localhost", "my_user", "my_password", "test");
mysqli_query($link, "DROP TABLE IF EXISTS friends");
mysqli_query($link, "CREATE TABLE friends (id int, name varchar(20))");
mysqli_query($link, "INSERT INTO friends VALUES (1,'Hartmut'), (2, 'Ulf')");
mysqli_real_query($link, $HTTP_POST_VARS['query']);
if (mysqli_field_count($link)) {
/* this was a select/show or describe query */
$result = mysqli_store_result($link);
/* process resultset */
$row = mysqli_fetch_row($result);
/* free resultset */
mysqli_free_result($result);
}
/* close connection */
mysqli_close($link);
?>