PHP mysql_fetch_array function

 The PHP mysql_fetch_array function is an extended function of mysql_fetch_row . It adds a parameter. The result set of mysql_query can be stored as a result of PHP Array in the form of a numeric index or a related index (with a field as a key name) . It provides more than mysql_fetch_row Richer application methods and convenient calling.

Basic syntax of PHP mysql_fetch_array function

array mysql_fetch_array ( resource $result , int $result_type )

There are two parameters in the basic syntax. The first parameter $result is the result set of mysql_query , which is a necessary item, and the second parameter $result_type is the key to control the storage key name. There are three options available, as shown below.

• MYSQL_NUM-get only numeric index (similar to the result of mysql_fetch_row )
  
• MYSQL_BOTH-The default value of mysql_fetch_array, which can be a numeric index or a related index
  
• MYSQL_ASSOC-get only related indexes (indexes are fields)
  

Some designers may be a little curious, what is the difference between storing as a digital index and a related index? The answer is when the subsequent PHP script calls this result set, which method can be used, the following three examples can be prepared to express the difference.

PHP mysql_fetch_array function example 1. Use MYSQL_NUM

<?
mysql_connect("localhost", "mysql_user", "mysql_password") or die("Could not connect DB.");
mysql_select_db("TestDB");
$result = mysql_query("SELECT test_id,test_name FROM topic");
while ($row = mysql_fetch_array($result, MYSQL_NUM)) {
　printf ("TID: %s  NAME: %s", $row[0], $row[1]);
}
?>

The first example is stored in a numeric index, so when you finally call the result, you can directly use the wording of $row[0] and $row[1], but you cannot use $row[test_id] and $row[test_name]. Writing.

PHP mysql_fetch_array function example 2: Use MYSQL_BOTH

<?
mysql_connect("localhost", "mysql_user", "mysql_password") or die("Could not connect DB.");
mysql_select_db("TestDB");
$result = mysql_query("SELECT test_id,test_name FROM topic");
while ($row = mysql_fetch_array($result, MYSQL_BOTH)) {
　printf ("TID: %s  NAME: %s", $row[0], $row[1]);
}
?>

The second example uses the MYSQL_BOTH parameter, so when calling, it is feasible to use $row[0], $row[1] or $row[test_id], $row[test_name].

PHP mysql_fetch_array function example 3. Use MYSQL_ASSOC

<?
mysql_connect("localhost", "mysql_user", "mysql_password") or die("Could not connect DB.");
mysql_select_db("TestDB");
$result = mysql_query("SELECT test_id,test_name FROM topic");
while ($row = mysql_fetch_array($result, MYSQL_ASSOC)) {
　printf ("TID: %s  NAME: %s", $row[test_id], $row[test_name]);
}
?>

Example 3 uses the MYSQL_ASSOC parameter, so in the final call, you can only use the wording of $row[test_id], $row[test_name], and the call method using numeric index will not be able to get the array value.

The above is the usage of PHP mysql_fetch_array function and the difference of the three parameters. Please adjust it according to your needs.