====== metaForeignKeys ======
~~NOTOC~~
<WRAP right box>
== Syntax ==
    mixed metaForeignKeys(
        string $tableName,
        optional string $owner='',
        optional bool $upperCase=false,
        optional bool $associative=false
        )
</WRAP>
===== Description =====
The function ''metaForeignKeys()'' returns an array of the foreign keys associated with a specific table. If there are no foreign keys then the function returns false.
===== Optional Parameters =====
==== $owner ====
If specified, only returns foreign keys associated with a table owned by that name. Some drivers discard this parameter
==== $upper ====
if specified, the table and columns are returned in uppercase. Default is lowercase.
==== $associative====
If specified, returns the result in associative mode. If ADODB_FETCH_MODE is already associative, then this parameter is discarded.
===== Return Value =====
The method returns an array of data:
  * The main key represents the foreign table that the key associated with.
  * The values of the key are either 
    * a key=>value pair, the key being the column name of the source table and the value being the column name of the foreign table if the request is //associative//, or 
    * a numeric key with value being the same data represented as ''local_column=foreign_column''.

===== Explanation =====
A table **//parent_table//** has a foreign key that references **//foreign_table//**. **//parent_table//** has 2 columns **//parent_id//** and **//parent_type//**. These 2 columns reference corresponding columns in **//foreign_table//**, **//foreign_id//** and **//foreign_type//**. ''metaForeignKeys('parent_table')'' presents this data in the following way:
==== Associative Mode ==== 
<code php>
[
    ['foreign_table'] [
        ['parent_id'] => 'foreign_id',
        ['parent_type'] => 'foreign_type'
    ]
]
</code>
==== Numeric Mode ====
<code php>
[
    ['foreign_table'] => [
        [0] => 'parent_id=foreign_id',
        [1] => 'parent_type=foreign_type'
    ]
]
</code>
===== Usage =====
<code php>
/*
 * Connection to MySql Employees Sample database
*/
$db->setFetchMode(ADODB_FETCH_NUM);

$p = $db->metaForeignKeys('dept_emp');
print_r($p);
/*
 * prints
Array
(
    [employees] => Array
        (
            [0] => emp_no=emp_no
        )

    [departments] => Array
        (
            [0] => dept_no=dept_no
        )

)
*/
</code>
==== Same Code In Associative Mode ====
<code php>
$db->setFetchMode(ADODB_FETCH_ASSOC);

$p = $db->metaForeignKeys('dept_emp');
print_r($p);
/*
 * prints
Array
(
    [employees] => Array
        (
            [emp_no]=>emp_no
        )

    [departments] => Array
        (
            [dept_no]=>dept_no
        )

)
*/
</code>