source: trunk/phpgwapi/inc/adodb/pivottable.inc.php @ 2

<?php
/** 
 * @version V4.50 6 July 2004 (c) 2000-2004 John Lim (jlim@natsoft.com.my). All rights reserved.
 * Released under both BSD license and Lesser GPL library license. 
 * Whenever there is any discrepancy between the two licenses, 
 * the BSD license will take precedence. 
 *
 * Set tabs to 4 for best viewing.
 * 
 * Latest version is available at http://php.weblogs.com
 *
 * Requires PHP4.01pl2 or later because it uses include_once
*/

/*
 * Concept from daniel.lucazeau@ajornet.com. 
 *
 * @param db            Adodb database connection
 * @param tables        List of tables to join
 * @rowfields           List of fields to display on each row
 * @colfield            Pivot field to slice and display in columns, if we want to calculate
 *                                              ranges, we pass in an array (see example2)
 * @where                       Where clause. Optional.
 * @aggfield            This is the field to sum. Optional. 
 *                                              Since 2.3.1, if you can use your own aggregate function 
 *                                              instead of SUM, eg. $sumfield = 'AVG(fieldname)';
 * @sumlabel            Prefix to display in sum columns. Optional.
 * @aggfn                       Aggregate function to use (could be AVG, SUM, COUNT)
 * @showcount           Show count of records
 *
 * @returns                     Sql generated
 */
 
 function PivotTableSQL($db,$tables,$rowfields,$colfield, $where=false,
        $aggfield = false,$sumlabel='Sum ',$aggfn ='SUM', $showcount = true)
 {
        if ($aggfield) $hidecnt = true;
        else $hidecnt = false;
        
        
        //$hidecnt = false;
        
        if ($where) $where = "\nWHERE $where";
        if (!is_array($colfield)) $colarr = $db->GetCol("select distinct $colfield from $tables $where order by 1");
        if (!$aggfield) $hidecnt = false;
        
        $sel = "$rowfields, ";
        if (is_array($colfield)) {
                foreach ($colfield as $k => $v) {
                        if (!$hidecnt) $sel .= "\n\t$aggfn(CASE WHEN $v THEN 1 ELSE 0 END) AS \"$k\", ";
                        if ($aggfield)
                                $sel .= "\n\t$aggfn(CASE WHEN $v THEN $aggfield ELSE 0 END) AS \"$sumlabel$k\", ";
                } 
        } else {
                foreach ($colarr as $v) {
                        if (!is_numeric($v)) $vq = $db->qstr($v);
                        else $vq = $v;
                        if (strlen($v) == 0     ) $v = 'null';
                        if (!$hidecnt) $sel .= "\n\t$aggfn(CASE WHEN $colfield=$vq THEN 1 ELSE 0 END) AS \"$v\", ";
                        if ($aggfield) {
                                if ($hidecnt) $label = $v;
                                else $label = "{$v}_$aggfield";
                                $sel .= "\n\t$aggfn(CASE WHEN $colfield=$vq THEN $aggfield ELSE 0 END) AS \"$label\", ";
                        }
                }
        }
        if ($aggfield && $aggfield != '1'){
                $agg = "$aggfn($aggfield)";
                $sel .= "\n\t$agg as \"$sumlabel$aggfield\", ";         
        }
        
        if ($showcount)
                $sel .= "\n\tSUM(1) as Total";
        else
                $sel = substr($sel,0,strlen($sel)-2);
        
        $sql = "SELECT $sel \nFROM $tables $where \nGROUP BY $rowfields";
        return $sql;
 }

/* EXAMPLES USING MS NORTHWIND DATABASE */
if (0) {

# example1
#
# Query the main "product" table
# Set the rows to CompanyName and QuantityPerUnit
# and the columns to the Categories
# and define the joins to link to lookup tables 
# "categories" and "suppliers"
#

 $sql = PivotTableSQL(
        $gDB,                                                                                   # adodb connection
        'products p ,categories c ,suppliers s',                # tables
        'CompanyName,QuantityPerUnit',                                  # row fields
        'CategoryName',                                                                 # column fields 
        'p.CategoryID = c.CategoryID and s.SupplierID= p.SupplierID' # joins/where
);
 print "<pre>$sql";
 $rs = $gDB->Execute($sql);
 rs2html($rs);
 
/*
Generated SQL:

SELECT CompanyName,QuantityPerUnit, 
        SUM(CASE WHEN CategoryName='Beverages' THEN 1 ELSE 0 END) AS "Beverages", 
        SUM(CASE WHEN CategoryName='Condiments' THEN 1 ELSE 0 END) AS "Condiments", 
        SUM(CASE WHEN CategoryName='Confections' THEN 1 ELSE 0 END) AS "Confections", 
        SUM(CASE WHEN CategoryName='Dairy Products' THEN 1 ELSE 0 END) AS "Dairy Products", 
        SUM(CASE WHEN CategoryName='Grains/Cereals' THEN 1 ELSE 0 END) AS "Grains/Cereals", 
        SUM(CASE WHEN CategoryName='Meat/Poultry' THEN 1 ELSE 0 END) AS "Meat/Poultry", 
        SUM(CASE WHEN CategoryName='Produce' THEN 1 ELSE 0 END) AS "Produce", 
        SUM(CASE WHEN CategoryName='Seafood' THEN 1 ELSE 0 END) AS "Seafood", 
        SUM(1) as Total 
FROM products p ,categories c ,suppliers s  WHERE p.CategoryID = c.CategoryID and s.SupplierID= p.SupplierID 
GROUP BY CompanyName,QuantityPerUnit
*/
//=====================================================================

# example2
#
# Query the main "product" table
# Set the rows to CompanyName and QuantityPerUnit
# and the columns to the UnitsInStock for different ranges
# and define the joins to link to lookup tables 
# "categories" and "suppliers"
#
 $sql = PivotTableSQL(
        $gDB,                                                                           # adodb connection
        'products p ,categories c ,suppliers s',        # tables
        'CompanyName,QuantityPerUnit',                          # row fields
                                                                                                # column ranges
array(                                                                          
' 0 ' => 'UnitsInStock <= 0',
"1 to 5" => '0 < UnitsInStock and UnitsInStock <= 5',
"6 to 10" => '5 < UnitsInStock and UnitsInStock <= 10',
"11 to 15"  => '10 < UnitsInStock and UnitsInStock <= 15',
"16+" =>'15 < UnitsInStock'
),
        ' p.CategoryID = c.CategoryID and s.SupplierID= p.SupplierID', # joins/where
        'UnitsInStock',                                                         # sum this field
        'Sum'                                                                           # sum label prefix
);
 print "<pre>$sql";
 $rs = $gDB->Execute($sql);
 rs2html($rs);
 /*
 Generated SQL:
 
SELECT CompanyName,QuantityPerUnit, 
        SUM(CASE WHEN UnitsInStock <= 0 THEN UnitsInStock ELSE 0 END) AS "Sum  0 ", 
        SUM(CASE WHEN 0 < UnitsInStock and UnitsInStock <= 5 THEN UnitsInStock ELSE 0 END) AS "Sum 1 to 5", 
        SUM(CASE WHEN 5 < UnitsInStock and UnitsInStock <= 10 THEN UnitsInStock ELSE 0 END) AS "Sum 6 to 10", 
        SUM(CASE WHEN 10 < UnitsInStock and UnitsInStock <= 15 THEN UnitsInStock ELSE 0 END) AS "Sum 11 to 15", 
        SUM(CASE WHEN 15 < UnitsInStock THEN UnitsInStock ELSE 0 END) AS "Sum 16+",
        SUM(UnitsInStock) AS "Sum UnitsInStock", 
        SUM(1) as Total 
FROM products p ,categories c ,suppliers s  WHERE  p.CategoryID = c.CategoryID and s.SupplierID= p.SupplierID 
GROUP BY CompanyName,QuantityPerUnit
 */
}
?>