Detailed explanation of MySQL database functions (4)

This function is used to split the query result result into object variables. The usage method is almost the same as mysql_fetch_array(). The difference is that the data returned by this function is an object instead of an array. If result has no data, a false value is returned. Another thing worth noting is that the index of the retrieved object data can only be text and not numbers. This is due to the characteristics of the object. All property (PRoperty) names in the properties of object data cannot be numbers, so we have to use text strings as indexes. The parameter result_typ is a constant value, including the following constants: MYSQL_ASSOC, MYSQL_NUM and MYSQL_BOTH. Regarding speed, the processing speed of this function is almost the same as that of mysql_fetch_row() and mysql_fetch_array(). Which function to use depends on the requirements.

<?php
$link=mysql_pconnect("localhost","sunsoft","suixiang") or die("Could not connect");
mysql_select_db("stamp_db") or die("Could not select database" );
$query="SELECT last_name,first_name FROM president";
$result=mysql_query($query) or die("Query failed");
while($row=mysql_fetch_object($result))
printf("% s %s<BR>
",$row->last_name,$row->first_name);
mysql_free_result($result);
?>

(14) array mysql_fetch_row(int result);
As a Array Returns the next row of the given result set, or false if there are no more rows. Column values ​​are accessed as array elements, using the column index in the range 0 to mysql_num_fields()-1.

<?php
$link=mysql_pconnect("localhost","sunsoft","suixiang") or die("Could not connect");
mysql_select_db("stamp_db") or die("Could not select database" );
$query="SELECT last_name,first_name FROM president";
$result=mysql_query($query) or die("Query failed");
while($row=mysql_fetch_row($result))
printf("% s %s<BR>
",$row[0],$row[1]);
mysql_free_result($result);
?>

(15) string mysql_field_name(int result, int field_index);
Return The name of the given column of the result set.
col_num ranges from 0 to mysql_num_fields()-1.

<?php
$link=mysql_pconnect("localhost","sunsoft","suixiang") or die("Could not connect");
mysql_select_db( "stamp_db") or die("Could not select database");
$query="SELECT * FROM president";
$result=mysql_query($query) or die("Query failed");
for($i= 0;$i<mysql_num_fields($result);$i++)
{
printf("Name of column %d:",$i);
$name=mysql_field_name($result,$i);
if(!$ name)
print("No name available<BR>
");
else
print("$name<BR>
");
}
?>


(16) int mysql_field_seek(int result, int field_offset);
Sets the index for subsequent mysql_fetch_field() calls. The next call to mysql_fetch_field() issued without an explicit column number will return information for column col_num. Returns true if the search is successful, false otherwise.
col_num ranges from 0 to mysql_num_fields()-1.

<?php
$link=mysql_pconnect("localhost","sunsoft","suixiang") or die("Could not connect");
mysql_select_db( "stamp_db") or die("Could not select database");
$query="SELECT * FROM president";
$result=mysql_query($query) or die("Query failed");
for($i= 0;$i<mysql_num_fields($result);$i++)
{
printf("Information for column %d:<BR>
",$i);
if(!mysql_field_seek($result,$i))
{
print("Cannot seek to colum<BR>
");
continue;
}
$meta=mysql_fetch_field($result,$i);
if(!$meta)
{
print("No information available<BR>
");
continue;
}
print("<PRE>
");
printf("blob: %s
",$meta->blob);
printf("max_length: %s
",$meta->max_length);
printf("multiple_key: %s
",$meta->multiple_key);
printf("name: %s
",$meta->name) ;
printf("not_null: %s
",$meta->not_null);
printf("numeric: %s
",$meta->numeric);
printf("primary_key: %s
", $meta->primary_key);
printf("table: %s
",$meta->table);
printf("type: %s
",$meta->type);
printf("unique_key: %s
",$meta->unique_key);
printf ("unsigned: %s
",$meta->unsigned);
printf("zerofill: %s
",$meta->zerofill);
print("</PRE>
");
}
?>

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