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db2_num_fields

(no version information, might be only in CVS)

db2_num_fields --  Returns the number of fields contained in a result set

说明

int db2_num_fields ( resource stmt )

警告

本函数是实验性的。本函数的行为，包括函数名称以及其它任何关于本函数的文档可能会在没有通知的情况下随 PHP 以后的发布而改变。使用本函数风险自担。

Returns the number of fields contained in a result set. This is most useful for handling the result sets returned by dynamically generated queries, or for result sets returned by stored procedures, where your application cannot otherwise know how to retrieve and use the results.

参数

stmt

A valid statement resource containing a result set.

返回值

Returns an integer value representing the number of fields in the result set associated with the specified statement resource. Returns FALSE if the statement resource is not a valid input value.

例

例子 1. Retrieving the number of fields in a result set

The following example demonstrates how to retrieve the number of fields returned in a result set.

<?php

$sql = "SELECT id, name, breed, weight FROM animals ORDER BY breed";
$stmt = db2_prepare($conn, $sql);
db2_execute($stmt, $sql);
$columns = db2_num_fields($stmt);

echo "There are {$columns} columns in the result set.";
?>

上例将输出：

There are 4 columns in the result set.

参见

db2_execute()
db2_field_display_size()
db2_field_name()
db2_field_num()
db2_field_precision()
db2_field_scale()
db2_field_type()
db2_field_width()

后退起点前进
db2_next_result上一级db2_num_rows