pg_num_fields()

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

返回字段的数目

说明

pg_num_fields(resource $result): int

pg_num_fields()返回 PostgreSQL$result中的字段（列）数目。参数是由pg_query()函数返回的查询结果资源号。如果出错则返回-1。

Note:

本函数以前的名字为pg_numfields()。

参见pg_num_rows()和pg_affected_rows()。

Here is a simple example for using pg_num_feilds, pg_num_rows and pg_result together. I'm simply SELECTing * from a table named markie on the current pg_connect(). 
<?php
  $pgsql_conn = pg_connect("dbname=mark host=localhost");
  if (!$pgsql_conn) {
    print pg_last_error($pgsql_conn);
    exit;
  }
  $results = pg_query($pgsql_conn, "SELECT * FROM markie");
  echo "<table border=1>\n";
  for($lt = 0; $lt < pg_num_rows($results); $lt++) {
    echo "<tr>\n";
    for($gt = 0; $gt < pg_num_fields($results); $gt++) {
      echo "<td>" . pg_result($results, $lt, $gt) . "</td>\n";
    }
    echo "</tr>\n";
  }
  echo "</table>\n";
  pg_close($pgsql_conn);
?>
This code snippet will print out the rows and columns into a HTML table.
Regards, --mark