maxdb_field_count

maxdb::field_count

(PECL maxdb >= 1.0)

maxdb_field_count -- maxdb::field_count — Returns the number of columns for the most recent query

说明

过程化风格

int maxdb_field_count ( resource $link )

面向对象风格

int maxdb::field_count ( void )

Returns the number of columns for the most recent query on the connection represented by the link parameter. This function can be useful when using the maxdb_store_result() function to determine if the query should have produced a non-empty result set or not without knowing the nature of the query.

返回值

An integer representing the number of fields in a result set.

范例

Example #1 面向对象风格

  <?php
$maxdb  = new  maxdb ( "localhost" ,  "MONA" ,  "RED" ,  "DEMODB" );

 maxdb_report  ( MAXDB_REPORT_OFF );
 $maxdb -> query ( "DROP TABLE friends" );
 maxdb_report  ( MAXDB_REPORT_ERROR );

 $maxdb -> query (  "CREATE TABLE friends (id int, name varchar(20))" );

 $maxdb -> query (  "INSERT INTO friends VALUES (1,'Hartmut')" );
 $maxdb -> query (  "INSERT INTO friends VALUES (2, 'Ulf')" );

if ( $maxdb -> field_count ()) {
    
    $result  =  $maxdb -> store_result ();

    
    $row  =  $result -> fetch_row ();

    
    $result -> close ();
}

 
 $maxdb -> close ();
 ?>

Example #2 过程化风格

  <?php
$link  =  maxdb_connect ( "localhost" ,  "MONA" ,  "RED" ,  "DEMODB" );

 maxdb_report  ( MAXDB_REPORT_OFF );
 maxdb_query ( $link , "DROP TABLE friends" );
 maxdb_report  ( MAXDB_REPORT_ERROR );

 maxdb_query ( $link ,  "CREATE TABLE friends (id int, name varchar(20))" );

 maxdb_query ( $link ,  "INSERT INTO friends VALUES (1,'Hartmut')" );
 maxdb_query ( $link ,  "INSERT INTO friends VALUES (2, 'Ulf')" );

if ( maxdb_field_count ( $link )) {
    
    $result  =  maxdb_store_result ( $link );

    
    $row  =  maxdb_fetch_row ( $result );

    
    maxdb_free_result ( $result );
}

 
 maxdb_close ( $link );
 ?>

The above example produces no output.