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--- reference:getmedian [2015/07/18 04:06] – created mnewnham
+++ v5:reference:connection:getmedian [2025/10/06 16:38] (current) – mnewnham
@@ Line 1: / Line 1: @@
-====== GetMedian ======
+====== getMedian ======
 ~~NOTOC~~
 <WRAP right box>
 == Syntax ==
    mixed getMedian {
-         mixed string $table
+     string $table
-         mixed string $column
+     string $column
-         optional mixed string $where
+     optional string $where
   }
 </WRAP>
+The method getMedian() does not return a true [[https://en.wikipedia.org/wiki/Median|arithmetic median]] but simply returns the value of a specific column in a specified table closest to the middle of a record set, as specified by WHERE criteria.
-Returns the median value of $column for $table, or false if an error occurs.
+If the number of records in the recordset is an even number, it returns the lower of the 2 closest records.
-The $where clause is optional, but if used, the WHERE statement must include the requested column  as in "WHERE name > 'A'". If an error occurs, false is returned.
+Because the method does not perform an arithmetic operation on the returned data, it can be used on character fields as well as numeric.
+The $where clause is optional, but if used, the WHERE statement must begin with the keyword //**WHERE**//, as in "WHERE name > 'A'".
+If an error occurs or a median row cannot be determined (for example the table is empty), false is returned.
+------------------------------
 ==== Usage ====
 <code php>
@@ Line 22: / Line 29: @@
 $table = 'zip_codes';
 $column = 'population';
+$where  = 'WHERE zip_code IN (80401,80402,80403)';
+$medianPopulation = $db->getMedian($table,$column,$where);
-$medianPopulation = $db->getMedian($table,$column);
 </code>