diff --git a/course-work/Implementations/README.md b/course-work/Implementations/README.md
new file mode 100644
index 0000000..69fe8b3
--- /dev/null
+++ b/course-work/Implementations/README.md
@@ -0,0 +1,6 @@
+Фак. номер: 1901322039
+Име: Таньо Николов
+
+Проектът е за социалната мрежа LinkedIn
+
+Линк към Google Looker Studio (визуализации): https://lookerstudio.google.com/u/1/reporting/d6c9d2a7-3204-4297-8b81-b75feb668f5d/page/vFycF
\ No newline at end of file
diff --git a/course-work/Implementations/functions.sql b/course-work/Implementations/functions.sql
new file mode 100644
index 0000000..5d3f4a7
--- /dev/null
+++ b/course-work/Implementations/functions.sql
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+DELIMITER //
+
+CREATE FUNCTION GetMostLikedComment()
+RETURNS TEXT
+DETERMINISTIC
+READS SQL DATA
+BEGIN
+ DECLARE most_liked_comment INT;
+
+ RETURN (SELECT Content FROM USER_COMMENT ORDER BY Likes LIMIT 1);
+END //
+
+CREATE FUNCTION PostsCount()
+RETURNS INT
+DETERMINISTIC
+READS SQL DATA
+BEGIN
+ RETURN (SELECT COUNT(*) FROM POST);
+END //
+
+-- Usage example
+-- SELECT GetMostLikedComment() as 'Most liked comment';
\ No newline at end of file
diff --git a/course-work/Implementations/linkedin-conceptional-model.drawio b/course-work/Implementations/linkedin-conceptional-model.drawio
new file mode 100644
index 0000000..b8bfa53
--- /dev/null
+++ b/course-work/Implementations/linkedin-conceptional-model.drawio
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diff --git a/course-work/Implementations/linkedin-db.sql b/course-work/Implementations/linkedin-db.sql
new file mode 100644
index 0000000..fac94dc
--- /dev/null
+++ b/course-work/Implementations/linkedin-db.sql
@@ -0,0 +1,180 @@
+DROP DATABASE IF EXISTS linkedin;
+
+CREATE DATABASE IF NOT EXISTS linkedin;
+
+USE linkedin;
+
+CREATE TABLE USER (
+ UserID INT AUTO_INCREMENT PRIMARY KEY,
+ Name VARCHAR(100) NOT NULL,
+ Email VARCHAR(150) NOT NULL UNIQUE,
+ Headline VARCHAR(255),
+ Location VARCHAR(100),
+ Summary TEXT,
+ CreatedAt TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
+ UpdatedAt TIMESTAMP DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP
+);
+
+CREATE TABLE COMPANY (
+ CompanyID INT AUTO_INCREMENT PRIMARY KEY,
+ CompanyName VARCHAR(200) NOT NULL,
+ Website VARCHAR(255),
+ Industry VARCHAR(100),
+ Size VARCHAR(50),
+ CreatedAt TIMESTAMP DEFAULT CURRENT_TIMESTAMP
+);
+
+CREATE TABLE POST (
+ PostID INT AUTO_INCREMENT PRIMARY KEY,
+ UserID INT NOT NULL,
+ Content TEXT NOT NULL,
+ CreatedAt TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
+ UpdatedAt TIMESTAMP DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
+ FOREIGN KEY (UserID) REFERENCES USER(UserID)
+);
+
+CREATE TABLE JOB_POSTING (
+ JobID INT AUTO_INCREMENT PRIMARY KEY,
+ CompanyID INT NOT NULL,
+ Title VARCHAR(200) NOT NULL,
+ Description TEXT,
+ Location VARCHAR(100),
+ Requirements TEXT,
+ PostedDate DATE,
+ ExpiryDate DATE,
+ FOREIGN KEY (CompanyID) REFERENCES COMPANY(CompanyID)
+);
+
+CREATE TABLE MESSAGE (
+ MessageID INT AUTO_INCREMENT PRIMARY KEY,
+ SenderID INT NOT NULL,
+ ReceiverID INT NOT NULL,
+ Content TEXT,
+ Timestamp TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
+ FOREIGN KEY (SenderID) REFERENCES USER(UserID),
+ FOREIGN KEY (ReceiverID) REFERENCES USER(UserID)
+);
+
+CREATE TABLE SKILL (
+ SkillID INT AUTO_INCREMENT PRIMARY KEY,
+ SkillName VARCHAR(100) NOT NULL
+);
+
+CREATE TABLE EDUCATION (
+ EducationID INT AUTO_INCREMENT PRIMARY KEY,
+ Degree VARCHAR(100),
+ InstitutionName VARCHAR(200),
+ StartDate DATE,
+ EndDate DATE,
+ Grade VARCHAR(50)
+);
+
+
+CREATE TABLE USER_COMMENT (
+ UserCommentID INT AUTO_INCREMENT PRIMARY KEY,
+ UserID INT NOT NULL,
+ PostID INT NOT NULL,
+ Content TEXT,
+ Likes INT,
+ FOREIGN KEY (PostID) REFERENCES POST(PostID)
+);
+
+
+CREATE TABLE WORK_EXPERIENCE (
+ ExperienceID INT AUTO_INCREMENT PRIMARY KEY,
+ UserID INT NOT NULL,
+ CompanyID INT NOT NULL,
+ JobTitle VARCHAR(150),
+ StartDate DATE,
+ EndDate DATE,
+ Description TEXT,
+ IsCurrent BOOLEAN DEFAULT FALSE,
+ FOREIGN KEY (UserID) REFERENCES USER(UserID),
+ FOREIGN KEY (CompanyID) REFERENCES COMPANY(CompanyID)
+);
+
+CREATE TABLE USER_SKILL (
+ UserSkillID INT AUTO_INCREMENT PRIMARY KEY,
+ UserID INT NOT NULL,
+ SkillID INT NOT NULL,
+ EndorsementCount INT DEFAULT 0,
+ FOREIGN KEY (UserID) REFERENCES USER(UserID),
+ FOREIGN KEY (SkillID) REFERENCES SKILL(SkillID)
+);
+
+CREATE TABLE USER_EDUCATION (
+ UserEducationID INT AUTO_INCREMENT PRIMARY KEY,
+ UserID INT NOT NULL,
+ EducationID INT NOT NULL,
+ StartDate DATE,
+ EndDate DATE,
+ Grade VARCHAR(20),
+ FOREIGN KEY (UserID) REFERENCES USER(UserID),
+ FOREIGN KEY (EducationID) REFERENCES EDUCATION(EducationID)
+);
+
+
+CREATE TABLE POST_REACTION (
+ ReactionID INT AUTO_INCREMENT PRIMARY KEY,
+ UserID INT NOT NULL,
+ PostID INT NOT NULL,
+ ReactionType ENUM('like', 'celebrate', 'love', 'insightful', 'curious'),
+ CreatedAt TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
+ FOREIGN KEY (UserID) REFERENCES USER(UserID),
+ FOREIGN KEY (PostID) REFERENCES POST(PostID)
+);
+
+
+INSERT INTO USER (Name, Email, Headline, Location, Summary) VALUES
+('Ivan Petrov', 'ivan.petrov@example.com', 'Senior Software Engineer', 'Sofia, Bulgaria', 'Experienced full-stack developer specializing in cloud solutions.'),
+('Maria Dimitrova', 'maria.dimitrova@example.com', 'Product Manager', 'Plovdiv, Bulgaria', 'Leading cross-functional teams to deliver SaaS products.');
+
+INSERT INTO COMPANY (CompanyName, Website, Industry, Size) VALUES
+('Cognify Labs Ltd', 'https://cognifylabs.com', 'Information Technology', '50-200'),
+('TechBridge Solutions', 'https://techbridgesolutions.com', 'Financial Services', '100-500');
+
+INSERT INTO SKILL (SkillName) VALUES
+('AWS Certified Developer'),
+('Project Management'),
+('TypeScript'),
+('React');
+
+INSERT INTO EDUCATION (Degree, InstitutionName, StartDate, EndDate, Grade) VALUES
+('MSc Computer Science', 'Plovdiv University', '2016-09-01', '2018-06-30', 'Excellent'),
+('BA Business Administration', 'Sofia University', '2012-09-01', '2016-06-30', 'Good');
+
+INSERT INTO USER_SKILL (UserID, SkillID, EndorsementCount) VALUES
+(1, 1, 6),
+(1, 3, 12),
+(2, 2, 4),
+(2, 4, 8);
+
+INSERT INTO USER_EDUCATION (UserID, EducationID, StartDate, EndDate, Grade) VALUES
+(1, 1, '2016-09-01', '2018-06-30', 'Excellent'),
+(2, 2, '2012-09-01', '2016-06-30', 'Good');
+
+INSERT INTO POST (UserID, Content) VALUES
+(1, 'Excited to join Cognify Labs and work on cloud-native projects!'),
+(2, 'Thrilled to announce our new B2B platform release!');
+
+
+INSERT INTO MESSAGE (SenderID, ReceiverID, Content) VALUES
+(1, 2, 'Welcome to the team, Maria!'),
+(2, 1, 'Thanks, Ivan! Looking forward to working together.');
+
+INSERT INTO WORK_EXPERIENCE (UserID, CompanyID, JobTitle, StartDate, EndDate, IsCurrent) VALUES
+(1, 1, 'Senior Software Engineer', '2019-01-01', NULL, TRUE),
+(2, 2, 'Product Manager', '2022-04-01', NULL, TRUE);
+
+INSERT INTO JOB_POSTING (CompanyID, Title, Description, Location, Requirements, PostedDate, ExpiryDate) VALUES
+(1, 'Full-Stack Developer', 'Join us to build scalable web applications.', 'Remote', 'React, Node.js, AWS', '2025-10-01', '2025-12-31'),
+(2, 'Data Analyst', 'Work with our fintech platform data sets.', 'Plovdiv', 'SQL, Python, Excel', '2025-09-15', '2025-11-30');
+
+INSERT INTO POST_REACTION (UserID, PostID, ReactionType) VALUES
+(2, 1, 'celebrate'),
+(1, 2, 'insightful');
+
+INSERT INTO USER_COMMENT (UserID, PostID, Content, Likes) VALUES
+(1, 2, "Great product!Will try it myself.", 3),
+(2, 1, "Congrats on your new role!!!", 1);
+
diff --git a/course-work/Implementations/linkedin-logical-model.drawio b/course-work/Implementations/linkedin-logical-model.drawio
new file mode 100644
index 0000000..04058f5
--- /dev/null
+++ b/course-work/Implementations/linkedin-logical-model.drawio
@@ -0,0 +1,4259 @@
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diff --git a/course-work/Implementations/linkedin-physical-model.drawio b/course-work/Implementations/linkedin-physical-model.drawio
new file mode 100644
index 0000000..4dcaf5e
--- /dev/null
+++ b/course-work/Implementations/linkedin-physical-model.drawio
@@ -0,0 +1,324 @@
+
+
+
diff --git a/course-work/Implementations/stored-procedures.sql b/course-work/Implementations/stored-procedures.sql
new file mode 100644
index 0000000..f708d18
--- /dev/null
+++ b/course-work/Implementations/stored-procedures.sql
@@ -0,0 +1,39 @@
+DELIMITER //
+
+CREATE PROCEDURE GetUserProfileSummary(IN p_UserID INT)
+BEGIN
+ SELECT UserID, Name, Email, Headline, Location, Summary
+ FROM USER
+ WHERE UserID = p_UserID;
+
+ -- TotalPosts
+ SELECT COUNT(*) AS TotalPosts
+ FROM POST
+ WHERE UserID = p_UserID;
+
+ -- Skills
+ SELECT s.SkillName, us.EndorsementCount
+ FROM USER_SKILL us
+ JOIN SKILL s ON us.SkillID = s.SkillID
+ WHERE us.UserID = p_UserID
+ ORDER BY us.EndorsementCount DESC;
+
+ -- Work experience
+ SELECT c.CompanyName, we.JobTitle, we.StartDate, we.EndDate, we.IsCurrent
+ FROM WORK_EXPERIENCE we
+ JOIN COMPANY c ON we.CompanyID = c.CompanyID
+ WHERE we.UserID = p_UserID
+ ORDER BY we.StartDate DESC;
+END //
+
+CREATE PROCEDURE MostUsedSkills()
+BEGIN
+ SELECT s.SkillName, COUNT(u.UserID)
+ FROM USER_SKILL us
+ JOIN USER u ON us.UserID = u.UserID
+ JOIN SKILL s ON us.SkillID = s.SkillID
+ GROUP BY s.SkillName;
+END //
+
+-- Usage example:
+-- CALL GetUserProfileSummary(1);
diff --git a/course-work/Implementations/triggers.sql b/course-work/Implementations/triggers.sql
new file mode 100644
index 0000000..1b39396
--- /dev/null
+++ b/course-work/Implementations/triggers.sql
@@ -0,0 +1,21 @@
+DELIMITER //
+
+CREATE TRIGGER SendNotificationMessageToThePostCreator
+BEFORE INSERT ON USER_COMMENT
+FOR EACH ROW
+BEGIN
+ SET @PostCreatorID = (SELECT UserID FROM POST WHERE PostID = NEW.PostID);
+ SET @CommentContent = NEW.Content;
+
+ INSERT INTO MESSAGE (SenderID, ReceiverID, Content) VALUES (@PostCreatorID, @PostCreatorID, @CommentContent);
+END //
+
+CREATE TRIGGER SendReactionNotification
+BEFORE INSERT ON POST_REACTION
+FOR EACH ROW
+BEGIN
+ SET @PostCreatorID = (SELECT UserID FROM POST WHERE PostID = NEW.PostID);
+ SET @ReactionType = NEW.ReactionType;
+
+ INSERT INTO MESSAGE (SenderID, ReceiverID, Content) VALUES (@PostCreatorID, @PostCreatorID, @ReactionType);
+END //
diff --git a/course-work/Implementations/visualizations-screenshot.png b/course-work/Implementations/visualizations-screenshot.png
new file mode 100644
index 0000000..0d842a9
Binary files /dev/null and b/course-work/Implementations/visualizations-screenshot.png differ