Вы могли бы попробовать что-то вроде этого:
<?php
//NOTE: I AM USING PDO FOR SIMPLICITY... BUT ANY OTHER DBAL WORKS AS WELL...
//DATABASE CONNECTION CONFIGURATION:
defined("HOST") or define("HOST", "localhost"); //REPLACE WITH YOUR DB-HOST
defined("DBASE") or define("DBASE", "_TEST_"); //REPLACE WITH YOUR DB NAME
defined("USER") or define("USER", "root"); //REPLACE WITH YOUR DB-USER
defined("PASS") or define("PASS", "root"); //REPLACE WITH YOUR DB-PASS
try {
$dbh = new PDO('mysql:host='.HOST.';dbname='. DBASE,USER,PASS);
$dbh->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
$sql = 'SELECT COUNT(SS.ID) AS "Global_Student_Population" FROM student_schedule AS SS ';
$stmt = $dbh->prepare($sql);
$stmt->execute();
$result = $stmt->fetchAll(PDO::FETCH_COLUMN);
$intAllStudents = (int)$result[0];
$sql = " SELECT BD.Ethnicity, {$intAllStudents} AS Global_Student_Population,
COUNT(DISTINCT SS.ID) AS Ethnic_Student_Population,
ROUND(COUNT(DISTINCT SS.ID)*100/{$intAllStudents}) AS '%_of_AS_Population'
FROM student_schedule AS SS
LEFT JOIN bday AS BD ON SS.ID=BD.ID
WHERE SS.Course LIKE 'AS%' GROUP BY BD.Ethnicity";
$stmt = $dbh->prepare($sql);
$stmt->execute();
$result = $stmt->fetchAll();
var_dump($result);
var_dump($intAllStudents);
//GARBAGE COLLECTION
$dbh = null;
}catch(PDOException $e){
echo $e->getMessage();
}
Мой var_dump() показывает что-то вроде этого:
array (size=3)
0 =>
array (size=8)
'Ethnicity' => string 'Black' (length=5)
0 => string 'Black' (length=5)
'Global_Student_Population' => string '10' (length=2)
1 => string '10' (length=2)
'Ethnic_Student_Population' => string '3' (length=1)
2 => string '3' (length=1)
'%_of_AS_Population' => string '30' (length=2)
3 => string '30' (length=2)
1 =>
array (size=8)
'Ethnicity' => string 'Hispanic' (length=8)
0 => string 'Hispanic' (length=8)
'Global_Student_Population' => string '10' (length=2)
1 => string '10' (length=2)
'Ethnic_Student_Population' => string '1' (length=1)
2 => string '1' (length=1)
'%_of_AS_Population' => string '10' (length=2)
3 => string '10' (length=2)
2 =>
array (size=8)
'Ethnicity' => string 'White' (length=5)
0 => string 'White' (length=5)
'Global_Student_Population' => string '10' (length=2)
1 => string '10' (length=2)
'Ethnic_Student_Population' => string '2' (length=1)
2 => string '2' (length=1)
'%_of_AS_Population' => string '20' (length=2)
3 => string '20' (length=2)
А вот мой тест Таблица Определения: - - Структура таблицы для таблицы bday -
CREATE TABLE `bday` (
`ID` int(11) NOT NULL,
`Ethnicity` varchar(255) NOT NULL
) ENGINE=InnoDB AUTO_INCREMENT=11 DEFAULT CHARSET=utf8;
--
-- Dumping data for table `bday`
--
INSERT INTO `bday` (`ID`, `Ethnicity`) VALUES
(1, 'Black'),
(2, 'Black'),
(3, 'Black'),
(4, 'White'),
(5, 'Hispanic'),
(6, 'White'),
(7, 'Asian'),
(8, 'Hispanic'),
(9, 'White'),
(10, 'Black');
--
-- Indexes for dumped tables
--
--
-- Indexes for table `bday`
--
ALTER TABLE `bday`
ADD PRIMARY KEY (`ID`);
--
-- AUTO_INCREMENT for dumped tables
--
--
-- AUTO_INCREMENT for table `bday`
--
ALTER TABLE `bday`
MODIFY `ID` int(11) NOT NULL AUTO_INCREMENT,AUTO_INCREMENT=11;
--
-- Table structure for table `student_schedule`
--
CREATE TABLE `student_schedule` (
`ID` int(11) unsigned NOT NULL,
`Course` varchar(255) NOT NULL
) ENGINE=InnoDB AUTO_INCREMENT=11 DEFAULT CHARSET=utf8;
--
-- Dumping data for table `student_schedule`
--
INSERT INTO `student_schedule` (`ID`, `Course`) VALUES
(1, 'AS'),
(2, 'AS'),
(3, 'EN'),
(4, 'EN'),
(5, 'AS'),
(6, 'AS'),
(7, 'EN'),
(8, 'EN'),
(9, 'AS'),
(10, 'AS');
--
-- Indexes for dumped tables
--
--
-- Indexes for table `student_schedule`
--
ALTER TABLE `student_schedule`
ADD PRIMARY KEY (`ID`);
--
-- AUTO_INCREMENT for dumped tables
--
--
-- AUTO_INCREMENT for table `student_schedule`
--
ALTER TABLE `student_schedule`
MODIFY `ID` int(11) unsigned NOT NULL AUTO_INCREMENT,AUTO_INCREMENT=11;
