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--- dictionary:metaforeignkeys [2015/08/12 02:05] – created mnewnham
+++ v5:dictionary:metaforeignkeys [2026/02/26 00:40] (current) – [Return Value] dregad
@@ Line 5: / Line 5: @@
     mixed metaForeignKeys(
         string $tableName,
-        optional string $owner=false,
+        optional string $owner='',
         optional bool $upperCase=false,
         optional bool $associative=false
@@ Line 14: / Line 14: @@
 ===== Optional Parameters =====
 ==== $owner ====
-If specified, only returns foreign keys associated with a table owned by that name.
+If specified, only returns foreign keys associated with a table owned by that name. Some drivers discard this parameter
 ==== $upper ====
-if specified, only matches the table with the uppercase name
+if specified, the table and columns are returned in uppercase. Default is lowercase.
 ==== $associative====
-If specified, returns the result in associative mode. If ADODB_FETCH_MODE is already associative, then this parameter is discarded
+If specified, returns the result in associative mode. If ADODB_FETCH_MODE is already associative, then this parameter is discarded.
+===== Return Value =====
+The method returns an array of data:
+  * The main key represents the foreign table that the key associated with.
+  * The values of the key are either
+    * a key=>value pair, the key being the column name of the source table and the value being the column name of the foreign table if the request is //associative//, or
+    * a numeric key with value being the same data represented as ''local_column=foreign_column''.
+===== Explanation =====
+A table **//parent_table//** has a foreign key that references **//foreign_table//**. **//parent_table//** has 2 columns **//parent_id//** and **//parent_type//**. These 2 columns reference corresponding columns in **//foreign_table//**, **//foreign_id//** and **//foreign_type//**. ''metaForeignKeys('parent_table')'' presents this data in the following way:
+==== Associative Mode ====
+<code php>
+[
+    ['foreign_table'] [
+        ['parent_id'] => 'foreign_id',
+        ['parent_type'] => 'foreign_type'
+    ]
+]
+</code>
+==== Numeric Mode ====
+<code php>
+[
+    ['foreign_table'] => [
+        [0] => 'parent_id=foreign_id',
+        [1] => 'parent_type=foreign_type'
+    ]
+]
+</code>
 ===== Usage =====
-<WRAP todo>
+<code php>
-Add Example of this
+/*
-</WRAP>
+ * Connection to MySql Employees Sample database
+*/
+$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>