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