diff --git a/Portifolio b/Portifolio
index bccb166..61841b5 100755
Binary files a/Portifolio and b/Portifolio differ
diff --git a/app.db b/app.db
index 4d8c3da..ce7c245 100644
Binary files a/app.db and b/app.db differ
diff --git a/internal/database/main.go b/internal/database/main.go
index b261c64..c32598d 100644
--- a/internal/database/main.go
+++ b/internal/database/main.go
@@ -55,7 +55,8 @@ func InitDB(db *sql.DB) {
         FOREIGN KEY (company_id)  REFERENCES companies(id),
         FOREIGN KEY (currency_id) REFERENCES currencies(id),
         FOREIGN KEY (category_id) REFERENCES category(id),
-        FOREIGN KEY (period_id)   REFERENCES periods(id)
+        FOREIGN KEY (period_id)   REFERENCES periods(id),
+        UNIQUE(company_id, category_id, period_id)
     );`
 
 	if _, err := db.Exec(schema); err != nil {
@@ -63,3 +64,37 @@ func InitDB(db *sql.DB) {
 	}
 	fmt.Println("Tables ready")
 }
+
+func MigrateAddUniqueToRevenueEntries(db *sql.DB) error {
+	steps := []string{
+		// 1. copy existing data into a temp table with the new constraint
+		`CREATE TABLE IF NOT EXISTS revenue_entries_new (
+			id          INTEGER PRIMARY KEY AUTOINCREMENT,
+			company_id  INTEGER NOT NULL,
+			currency_id INTEGER NOT NULL,
+			category_id INTEGER NOT NULL,
+			period_id   INTEGER NOT NULL,
+			value       REAL    NOT NULL,
+			FOREIGN KEY (company_id)  REFERENCES companies(id),
+			FOREIGN KEY (currency_id) REFERENCES currencies(id),
+			FOREIGN KEY (category_id) REFERENCES category(id),
+			FOREIGN KEY (period_id)   REFERENCES periods(id),
+			UNIQUE(company_id, category_id, period_id)
+		)`,
+		// 2. copy data over
+		`INSERT OR IGNORE INTO revenue_entries_new
+			SELECT id, company_id, currency_id, category_id, period_id, value
+			FROM revenue_entries`,
+		// 3. drop old table
+		`DROP TABLE revenue_entries`,
+		// 4. rename new table
+		`ALTER TABLE revenue_entries_new RENAME TO revenue_entries`,
+	}
+
+	for _, step := range steps {
+		if _, err := db.Exec(step); err != nil {
+			return fmt.Errorf("migration failed: %w", err)
+		}
+	}
+	return nil
+}
diff --git a/internal/database/revenue.go b/internal/database/revenue.go
index f76da0d..f033ac0 100644
--- a/internal/database/revenue.go
+++ b/internal/database/revenue.go
@@ -57,3 +57,59 @@ func GetPeriodByID(db *sql.DB, periodID int) (model.Period, error) {
 	p.End, _ = time.Parse("2006-01-02", end)
 	return p, nil
 }
+
+func GetRevenueByPeriod(db *sql.DB, companyID int, periodID int) ([]model.Revenue, error) {
+	rows, err := db.Query(
+		`SELECT id, company_id, currency_id, period_id, value FROM revenue_entries WHERE company_id = ? AND period_id = ?`,
+		companyID, periodID,
+	)
+	if err != nil {
+		return nil, fmt.Errorf("query revenue by period: %w", err)
+	}
+	defer rows.Close()
+
+	var revenues []model.Revenue
+	for rows.Next() {
+		var rc model.Revenue
+		if err := rows.Scan(&rc.ID, &rc.Company, &rc.Currency, &rc.Period, &rc.Value); err != nil {
+			return nil, fmt.Errorf("scan revenue row: %w", err)
+		}
+		revenues = append(revenues, rc)
+	}
+	if err := rows.Err(); err != nil {
+		return nil, fmt.Errorf("iterate revenue rows: %w", err)
+	}
+	if len(revenues) == 0 {
+		return nil, fmt.Errorf("revenue by company %d and period_id %d not found", companyID, periodID)
+	}
+
+	return revenues, nil
+}
+
+func GetRevenueByCategory(db *sql.DB, companyID int, categoryID int) ([]model.Revenue, error) {
+	rows, err := db.Query(
+		`SELECT id, company_id, currency_id, category_id, value FROM revenue_entries WHERE company_id = ? AND category_id = ?`,
+		companyID, categoryID,
+	)
+	if err != nil {
+		return nil, fmt.Errorf("query revenue by category: %w", err)
+	}
+	defer rows.Close()
+
+	var revenues []model.Revenue
+	for rows.Next() {
+		var rc model.Revenue
+		if err := rows.Scan(&rc.ID, &rc.Company, &rc.Currency, &rc.Category, &rc.Value); err != nil {
+			return nil, fmt.Errorf("scan revenue row: %w", err)
+		}
+		revenues = append(revenues, rc)
+	}
+	if err := rows.Err(); err != nil {
+		return nil, fmt.Errorf("iterate revenue rows: %w", err)
+	}
+	if len(revenues) == 0 {
+		return nil, fmt.Errorf("revenue by company %d and category_id %d not found", companyID, categoryID)
+	}
+
+	return revenues, nil
+}
diff --git a/internal/handlers/revenue.go b/internal/handlers/revenue.go
index 9e75b44..6e62adb 100644
--- a/internal/handlers/revenue.go
+++ b/internal/handlers/revenue.go
@@ -6,7 +6,6 @@ import (
 	"database/sql"
 	"encoding/json"
 	"net/http"
-	"strconv"
 
 	_ "github.com/mattn/go-sqlite3"
 )
@@ -51,6 +50,7 @@ func AddRevenueEntryHandler(db *sql.DB) http.HandlerFunc {
 	}
 }
 
+/*
 func GetRevenueReportHandler(db *sql.DB) http.HandlerFunc {
 	return func(w http.ResponseWriter, r *http.Request) {
 		companyID, _ := strconv.Atoi(r.URL.Query().Get("company_id"))
@@ -58,7 +58,7 @@ func GetRevenueReportHandler(db *sql.DB) http.HandlerFunc {
 		year, _ := strconv.Atoi(r.URL.Query().Get("year"))
 		idx, _ := strconv.Atoi(r.URL.Query().Get("index"))
 
-		entries, err := service.GetRevenue(db, companyID, model.PeriodType(periodType), year, idx)
+		entries, err := database.GetRevenueByPeriod(db, companyID, )
 		if err != nil {
 			http.Error(w, err.Error(), http.StatusInternalServerError)
 			return
@@ -68,3 +68,4 @@ func GetRevenueReportHandler(db *sql.DB) http.HandlerFunc {
 		json.NewEncoder(w).Encode(entries)
 	}
 }
+*/
diff --git a/internal/service/revenue.go b/internal/service/revenue.go
index b995b91..371207d 100644
--- a/internal/service/revenue.go
+++ b/internal/service/revenue.go
@@ -5,7 +5,6 @@ import (
 	"Portifolio/internal/model"
 	"database/sql"
 	"fmt"
-	"time"
 
 	_ "github.com/mattn/go-sqlite3"
 )
@@ -54,46 +53,3 @@ func InsertRevenue(db *sql.DB, companyID int, currencyID int, categoryName strin
 
 	return nil
 }
-
-func GetRevenue(db *sql.DB, companyID int, periodType model.PeriodType, year, idx int) ([]model.Revenue, error) {
-	rows, err := db.Query(`
-		WITH RECURSIVE tree AS (
-			SELECT id, name, parent_id
-			FROM category
-			WHERE company_id = ? AND parent_id IS NULL
-
-			UNION ALL
-
-			SELECT c.id, c.name, c.parent_id
-			FROM category c
-			JOIN tree t ON c.parent_id = t.id
-		)
-		SELECT e.id, t.name, e.value,
-		       p.type, p.year, p.idx, p.start_date, p.end_date
-		FROM revenue_entries e
-		JOIN tree t    ON e.category_id = t.id
-		JOIN periods p ON e.period_id   = p.id
-		WHERE e.company_id = ? AND p.type = ? AND p.year = ? AND p.idx = ?`,
-		companyID, companyID, string(periodType), year, idx,
-	)
-	if err != nil {
-		return nil, fmt.Errorf("query revenue: %w", err)
-	}
-	defer rows.Close()
-
-	var entries []model.Revenue
-	for rows.Next() {
-		var e model.Revenue
-		var p model.Period
-		var start, end string
-		if err := rows.Scan(&e.ID, &e.Category, &e.Value,
-			&p.Type, &p.Year, &p.Index, &start, &end); err != nil {
-			return nil, fmt.Errorf("scan revenue row: %w", err)
-		}
-		p.Start, _ = time.Parse("2006-01-02", start)
-		p.End, _ = time.Parse("2006-01-02", end)
-		e.Period = &p
-		entries = append(entries, e)
-	}
-	return entries, rows.Err()
-}
diff --git a/internal/shell/revenue.go b/internal/shell/revenue.go
index 3a05ae9..95a838d 100644
--- a/internal/shell/revenue.go
+++ b/internal/shell/revenue.go
@@ -122,7 +122,7 @@ func ListRevenue(scanner *bufio.Scanner, db *sql.DB) {
 		return
 	}
 
-	entries, err := service.GetRevenue(db, companyID, period.Type, period.Year, period.Index)
+	entries, err := database.GetRevenueByPeriod(db, companyID, period.ID)
 	if err != nil {
 		fmt.Println("  ✗ Error:", err)
 		return
diff --git a/main.go b/main.go
index 9cc4110..10624bd 100644
--- a/main.go
+++ b/main.go
@@ -30,6 +30,7 @@ func main() {
 	}
 
 	database.InitDB(db)
+	database.MigrateAddUniqueToRevenueEntries(db)
 	fmt.Println("Connected to SQLite database")
 
 	http.HandleFunc("/health", handlers.HealthHandler(db))
@@ -43,7 +44,7 @@ func main() {
 
 	// Revenue
 	http.HandleFunc("POST /add/revenue/entry", handlers.AddRevenueEntryHandler(db))
-	http.HandleFunc("GET /revenue/report", handlers.GetRevenueReportHandler(db))
+	//http.HandleFunc("GET /revenue/report", handlers.GetRevenueReportHandler(db))
 
 	fmt.Println("Server running on :8080")
 	go func() {