(PHP 5, PHP 7, PHP 8)
mysqli::$warning_count -- mysqli_warning_count — Returns the number of warnings generated by the most recently executed query
面向对象风格
过程化风格
Returns the number of warnings generated by the most recently executed query.
注意: For retrieving warning messages the following SQL command can be used:
SHOW WARNINGS [limit row_count].
Number of warnings or zero if there are no warnings.
示例 #1 $mysqli->warning_count example
面向对象风格
<?php
mysqli_report(MYSQLI_REPORT_ERROR | MYSQLI_REPORT_STRICT);
$mysqli = new mysqli("localhost", "my_user", "my_password", "world");
$mysqli->query("SELECT 42/0");
if ($mysqli->warning_count > 0) {
$result = $mysqli->query("SHOW WARNINGS");
$row = $result->fetch_row();
printf("%s (%d): %s\n", $row[0], $row[1], $row[2]);
}过程化风格
<?php
mysqli_report(MYSQLI_REPORT_ERROR | MYSQLI_REPORT_STRICT);
$link = mysqli_connect("localhost", "my_user", "my_password", "world");
mysqli_query($link, "SELECT 42/0");
if (mysqli_warning_count($link) > 0) {
$result = mysqli_query($link, "SHOW WARNINGS");
$row = mysqli_fetch_row($result);
printf("%s (%d): %s\n", $row[0], $row[1], $row[2]);
}以上示例会输出：
Warning (1365): Division by 0