PHP - Manual: maxdb_field_count
2024-12-23
(PECL maxdb >= 1.0)
maxdb_field_count -- maxdb::field_count — Returns the number of columns for the most recent query
过程化风格
$link
) : int面向对象风格
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 maxdb_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 面向对象风格
<?php
$maxdb = new maxdb("localhost", "MONA", "RED", "DEMODB");
maxdb_report (MAXDB_REPORT_OFF);
$maxdb->query("DROP TABLE friends");
maxdb_report (MAXDB_REPORT_ERROR);
$maxdb->query( "CREATE TABLE friends (id int, name varchar(20))");
$maxdb->query( "INSERT INTO friends VALUES (1,'Hartmut')");
$maxdb->query( "INSERT INTO friends VALUES (2, 'Ulf')");
if ($maxdb->field_count()) {
/* this was a select/show or describe query */
$result = $maxdb->store_result();
/* process resultset */
$row = $result->fetch_row();
/* free resultset */
$result->close();
}
/* close connection */
$maxdb->close();
?>
Example #2 过程化风格
<?php
$link = maxdb_connect("localhost", "MONA", "RED", "DEMODB");
maxdb_report (MAXDB_REPORT_OFF);
maxdb_query($link,"DROP TABLE friends");
maxdb_report (MAXDB_REPORT_ERROR);
maxdb_query($link, "CREATE TABLE friends (id int, name varchar(20))");
maxdb_query($link, "INSERT INTO friends VALUES (1,'Hartmut')");
maxdb_query($link, "INSERT INTO friends VALUES (2, 'Ulf')");
if (maxdb_field_count($link)) {
/* this was a select/show or describe query */
$result = maxdb_store_result($link);
/* process resultset */
$row = maxdb_fetch_row($result);
/* free resultset */
maxdb_free_result($result);
}
/* close connection */
maxdb_close($link);
?>
The above example produces no output.
官方地址:https://www.php.net/manual/en/function.maxdb-field-count.php