pg_field_prtlen
pg_field_prtlen
(PHP 4 >= 4.2.0, PHP 5, PHP 7)
pg_field_prtlen - 返回打印的长度
描述
int pg_field_prtlen ( resource $result , int $row_number , mixed $field_name_or_number )
int pg_field_prtlen ( resource $result , mixed $field_name_or_number )
pg_field_prtlen（）返回PostgreSQL中特定值的实际打印长度（字符数）result。行编号从0开始。此函数将返回FALSE一个错误。
field_name_or_number可以作为整数或字符串传递。如果以整数形式传递，PHP会将其识别为字段编号，否则将其视为字段名称。
请参阅pg_field_name（）页面中给出的示例。
注意：这个函数被称为pg_fieldprtlen（）。
参数
result
PostgreSQL查询结果资源，由pg_query（），pg_query_params（）或pg_execute（）等返回。
row
结果中的行号。行从0开始编号。如果省略，则取出当前行。
返回值
该字段打印长度或FALSE错误。
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
