structure preparation

db/Structure.sql

@@ -364,13 +364,11 @@ CREATE TABLE IF NOT EXISTS `specializations` (
 
 CREATE TABLE IF NOT EXISTS `students` (
   `ID` int(11) NOT NULL AUTO_INCREMENT,
-  `GroupID` int(11) NOT NULL,
   `AccountID` int(11) NOT NULL,
   `LastName` varchar(30) CHARACTER SET utf8 NOT NULL,
   `FirstName` varchar(30) CHARACTER SET utf8 NOT NULL,
   `SecondName` varchar(30) CHARACTER SET utf8 DEFAULT NULL,
   PRIMARY KEY (`ID`),
-  KEY `GroupID` (`GroupID`),
   KEY `AccountID` (`AccountID`)
 ) ENGINE=InnoDB  DEFAULT CHARSET=utf8;
 
@@ -516,6 +514,27 @@ CREATE TABLE IF NOT EXISTS `recovery_tokens` (
 
 
 
+-- --------------------------------------------------------
+
+--
+-- Структура таблицы `students_groups`
+--
+CREATE TABLE IF NOT EXISTS `students_groups` (
+  `ID` int(11) NOT NULL AUTO_INCREMENT,
+  `StudentID` int(11) NOT NULL,
+  `GroupID` int(11) NOT NULL,
+  `SemesterID` int(11) NOT NULL,
+  `IsStudyLeave` tinyint(1) NOT NULL DEFAULT '0',
+  `Date` date NULL,
+  PRIMARY KEY (`ID`),
+  UNIQUE KEY `StudentID_2` (`StudentID`,`GroupID`,`SemesterID`),
+  KEY `SemesterID` (`SemesterID`),
+  KEY `StudentID` (`StudentID`),
+  KEY `GroupID` (`GroupID`)
+) ENGINE=InnoDB DEFAULT CHARSET=utf8;
+
+
+
 --
 -- Дамп данных таблицы `user_roles`
 --
@@ -674,7 +693,6 @@ ALTER TABLE `specializations`
 -- Ограничения внешнего ключа таблицы `students`
 --
 ALTER TABLE `students`
-  ADD CONSTRAINT `students_ibfk_1` FOREIGN KEY (`GroupID`) REFERENCES `study_groups` (`ID`),
   ADD CONSTRAINT `students_ibfk_2` FOREIGN KEY (`AccountID`) REFERENCES `accounts` (`ID`);
 
 --
@@ -707,6 +725,15 @@ ALTER TABLE `subjects_faculties`
   ADD CONSTRAINT `subjects_faculties_ibfk_2` FOREIGN KEY (`SubjectID`) REFERENCES `subjects` (`ID`);
 
 
+--
+-- Ограничения внешнего ключа таблицы `students_groups`
+--
+ALTER TABLE  `students_groups`
+  ADD CONSTRAINT `students_groups_ibfk_1` FOREIGN KEY (`StudentID`) REFERENCES `students` (`ID`),
+  ADD CONSTRAINT `students_groups_ibfk_2` FOREIGN KEY (`GroupID`) REFERENCES `study_groups` (`ID`),
+  ADD CONSTRAINT `students_groups_ibfk_3` FOREIGN KEY (`SemesterID`) REFERENCES `semesters` (`ID`);
+
+
 
 /*!40101 SET CHARACTER_SET_CLIENT=@OLD_CHARACTER_SET_CLIENT */;
 /*!40101 SET CHARACTER_SET_RESULTS=@OLD_CHARACTER_SET_RESULTS */;

db/fix.sql

-ALTER TABLE `disciplines` CHANGE LectionCount LectureCount int(11) NOT NULL DEFAULT '0';
-
+# 5.03.15 - db refactoring
 
+ALTER TABLE `disciplines` CHANGE LectionCount LectureCount int(11) NOT NULL DEFAULT '0';
 
 ALTER TABLE students DROP FOREIGN KEY students_ibfk_1;
 ALTER TABLE disciplines_groups DROP FOREIGN KEY disciplines_groups_ibfk_2;
@@ -41,3 +41,42 @@ SET modules.OrderNum = 3141592
 WHERE modules.OrderNum = 3141692;
 
 
+
+
+# 15.03.15 - student's groups memorization
+
+CREATE TABLE IF NOT EXISTS `students_groups` (
+    `ID` int(11) NOT NULL AUTO_INCREMENT,
+    `StudentID` int(11) NOT NULL,
+    `GroupID` int(11) NOT NULL,
+    `SemesterID` int(11) NOT NULL,
+    `IsStudyLeave` tinyint(1) NOT NULL DEFAULT '0',
+    `Date` date NULL,
+    PRIMARY KEY (`ID`),
+    UNIQUE KEY `StudentID_2` (`StudentID`,`GroupID`,`SemesterID`),
+    KEY `SemesterID` (`SemesterID`),
+    KEY `StudentID` (`StudentID`),
+    KEY `GroupID` (`GroupID`)
+) ENGINE=InnoDB DEFAULT CHARSET=utf8;
+
+
+# constraints
+ALTER TABLE `students_groups`
+    ADD CONSTRAINT `students_groups_ibfk_1` FOREIGN KEY (`StudentID`) REFERENCES `students` (`ID`),
+    ADD CONSTRAINT `students_groups_ibfk_2` FOREIGN KEY (`GroupID`) REFERENCES `study_groups` (`ID`),
+    ADD CONSTRAINT `students_groups_ibfk_3` FOREIGN KEY (`SemesterID`) REFERENCES `semesters` (`ID`);
+
+# save groups
+INSERT INTO `students_groups` (StudentID, GroupID, SemesterID)
+SELECT DISTINCT students.ID, students.GroupID, semesters.ID
+    FROM `students`
+    CROSS JOIN `semesters`;
+
+# clear useless data
+ALTER TABLE  `students` DROP FOREIGN KEY  `students_ibfk_1` ;
+ALTER TABLE  `students` DROP INDEX  `GroupID` ;
+ALTER TABLE  `students` DROP  `GroupID` ;
+
+
+
+