PHP

pg_field_size

pg_field_size

(PHP 4 >= 4.2.0, PHP 5, PHP 7)

pg_field_size - 返回指定字段的内部存储大小

描述

int pg_field_size ( resource $result , int $field_number )

pg_field_size()返回给定PostgreSQL中字段号的内部存储大小(以字节为单位)result

注意:这个函数被称为pg_fieldsize()

参数

result

PostgreSQL查询结果资源,由pg_query(),pg_query_params()或pg_execute()等返回。

field_number

字段编号,从0开始。

返回值

内部字段存储大小(以字节为单位)。-1表示可变长度字段。FALSE错误返回。

例子

Example #1 Getting information about fields

<?php   $dbconn = pg_connect("dbname=publisher") or die("Could not connect"   $res = pg_query($dbconn, "select * from authors where author = 'Orwell'"   $i = pg_num_fields($res   for ($j = 0; $j < $i; $j++) {       echo "column $j\n";       $fieldname = pg_field_name($res, $j       echo "fieldname: $fieldname\n";       echo "printed length: " . pg_field_prtlen($res, $fieldname) . " characters\n";       echo "storage length: " . pg_field_size($res, $j) . " bytes\n";       echo "field type: " . pg_field_type($res, $j) . " \n\n";   } ?>

上面的例子将输出:

column 0 fieldname: author printed length: 6 characters storage length: -1 bytes field type: varchar column 1 fieldname: year printed length: 4 characters storage length: 2 bytes field type: int2 column 2 fieldname: title printed length: 24 characters storage length: -1 bytes field type: varchar