(PHP 5 >= 5.1.0, PHP 7, PECL pdo >= 0.2.0)
PDOStatement::columnCount — 锟斤拷锟截斤拷锟斤拷锟斤拷械锟斤拷锟斤拷锟�
使锟斤拷 PDOStatement::columnCount() 锟斤拷锟斤拷锟斤拷 PDOStatement 锟斤拷锟斤拷锟斤拷锟侥斤拷锟斤拷锟斤拷械锟斤拷锟斤拷锟斤拷锟�
锟斤拷锟斤拷锟斤拷锟� PDO::query() 锟斤拷锟截碉拷 PDOStatement 锟斤拷锟斤拷锟斤拷锟斤拷锟斤拷锟斤拷锟斤拷锟斤拷锟斤拷锟斤拷锟矫★拷
锟斤拷锟斤拷锟斤拷锟� PDO::prepare() 锟斤拷锟截碉拷 PDOStatement 锟斤拷锟斤拷锟斤拷锟节碉拷锟斤拷 PDOStatement::execute() 之前锟斤拷锟斤拷锟斤拷准确锟截硷拷锟斤拷锟斤拷锟斤拷锟斤拷锟�
锟斤拷锟斤拷锟斤拷 PDOStatement 锟斤拷锟斤拷锟斤拷锟侥斤拷锟斤拷锟斤拷械锟斤拷锟斤拷锟斤拷锟斤拷锟斤拷没锟叫斤拷锟斤拷锟斤拷锟斤拷锟� PDOStatement::columnCount() 锟斤拷锟斤拷 0锟斤拷
Example #1 锟斤拷锟斤拷锟斤拷锟斤拷
锟斤拷锟斤拷锟斤拷锟斤拷锟斤拷示锟斤拷锟绞癸拷锟� PDOStatement::columnCount() 锟斤拷锟斤拷一锟斤拷锟斤拷锟斤拷锟斤拷锟揭伙拷锟斤拷占锟斤拷锟�
<?php
$dbh = new PDO('odbc:sample', 'db2inst1', 'ibmdb2');
$sth = $dbh->prepare("SELECT name, colour FROM fruit");
/* 锟斤拷锟斤拷一锟斤拷锟斤拷锟斤拷锟斤拷锟节ｏ拷锟侥斤拷锟斤拷锟斤拷械锟斤拷锟斤拷锟� */
$colcount = $sth->columnCount();
print("Before execute(), result set has $colcount columns (should be 0)\n");
$sth->execute();
/* 锟斤拷锟斤拷锟斤拷锟斤拷锟叫碉拷锟斤拷锟斤拷 */
$colcount = $sth->columnCount();
print("After execute(), result set has $colcount columns (should be 2)\n");
?>
锟斤拷锟斤拷锟斤拷锟教伙拷锟斤拷锟斤拷锟�
Before execute(), result set has 0 columns (should be 0) After execute(), result set has 2 columns (should be 2)