Differences

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--- v5:reference:concat [2016/01/16 23:08] – [Concat] mnewnham
+++ v5:reference:connection:concat [2016/01/29 21:34] (current) – mnewnham
@@ Line 7: / Line 7: @@
 </WRAP>
 ===== Description =====
-The function ''concat()'' takes an input CSV list strings, and returns a database-specific string of concatenated values
+The function ''concat()'' takes an variable list of strings, and returns a database-specific string of concatenated values. It is important to recognize the difference between concatenating a database field or a string when using the method in an SQL statement
+-------------------------------
 ===== Usage =====
 <code php>
@@ Line 13: / Line 14: @@
  * Assume MySQL database
  */
-$list = 'VOGON,POETRY,READING';
+$string = $db->concat('VOGON','POETRY','READING');
-$string = $db->concat($list);
+/*
+ * Returns: CONCAT(VOGON,POETRY,READING)
+ * assuming that they are database columns
+*/
+</code>
+===== Concatenating Strings And Database Fields =====
+In order to concatenate database fields and strings together it is necessary to quote the strings
+<code php>
 /*
- * Returns: CONCAT(VOGON,POETRY,READING);
+* Best methodology
+*/
+$s = $db->quote(', Arthur Dent');
+$SQL = "UPDATE hitchhikers
+           SET last_name = {$db->concat(last_name,$s)}
+         WHERE first_name='Arthur'
+           AND last_name='Dent'";
+$db->execute($SQL);
+$SQL = "SELECT last_name FROM hitchhikers
+         WHERE first_name='Arthur'";
+print $db->getOne($SQL);
+/*
+* Prints "Dent, Arthur Dent"
 */
 </code>