array ( 0 => 'index.php', 1 => 'PHP Manual', ), 'head' => array ( 0 => 'UTF-8', 1 => 'zh', ), 'this' => array ( 0 => 'function.pg-field-size.php', 1 => 'pg_field_size', ), 'up' => array ( 0 => 'ref.pgsql.php', 1 => 'PostgreSQL 函数', ), 'prev' => array ( 0 => 'function.pg-field-prtlen.php', 1 => 'pg_field_prtlen', ), 'next' => array ( 0 => 'function.pg-field-table.php', 1 => 'pg_field_table', ), 'alternatives' => array ( ), 'source' => array ( 'lang' => 'zh', 'path' => 'reference/pgsql/functions/pg-field-size.xml', ), ); $setup["toc"] = $TOC; $setup["toc_deprecated"] = $TOC_DEPRECATED; $setup["parents"] = $PARENTS; manual_setup($setup); ?>
(PHP 4 >= 4.2.0, PHP 5, PHP 7, PHP 8)
pg_field_size — 返回指定字段的内部存储大小
pg_field_size() 返回指定 PostgreSQL result
中字段编号的内部存储大小(以字节为单位)。
注意:
本函数以前的名字为 pg_fieldsize()。
内部字段存储大小(以字节为单位)。-1 表示可变长度字段。
版本 | 说明 |
---|---|
8.1.0 |
现在 result 参数接受 PgSql\Result
实例,之前接受 resource。
|
示例 #1 获取字段信息
<?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";
}
?>
以上示例会输出:
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