SELECT
    u.urun_adi,
    COUNT(*) as satis_adedi,
    SUM(s.miktar) as toplam_miktar,
    SUM(s.miktar * s.birim_fiyat) as toplam_tutar
FROM satislar s
JOIN urunler u ON s.urun_id = u.id
WHERE MONTH(s.satis_tarihi) = 3
AND YEAR(s.satis_tarihi) = YEAR(CURRENT_DATE)
GROUP BY u.urun_adi
ORDER BY satis_adedi DESC
LIMIT 5

SELECT
    m.sehir,
    DATE_FORMAT(s.satis_tarihi, '%Y-%m') as ay,
    COUNT(DISTINCT m.musteri_id) as tekil_musteri,
    COUNT(*) as siparis_sayisi,
    SUM(s.tutar) as toplam_satis,
    ROUND(AVG(s.tutar), 2) as ortalama_siparis
FROM satislar s
JOIN musteriler m ON s.musteri_id = m.musteri_id
GROUP BY m.sehir, ay
ORDER BY m.sehir, ay DESC

SELECT
    u.urun_kodu,
    u.urun_adi,
    u.stok_miktari,
    u.minimum_stok,
    k.kategori_adi,
    t.tedarikci_adi,
    DATEDIFF(CURRENT_DATE, u.son_siparis_tarihi) as son_siparisten_gecen_gun
FROM urunler u
JOIN kategoriler k ON u.kategori_id = k.id
JOIN tedarikciler t ON u.tedarikci_id = t.id
WHERE u.stok_miktari <= u.minimum_stok
ORDER BY
    (u.stok_miktari / u.minimum_stok) ASC,
    son_siparisten_gecen_gun DESC

WITH musteri_analiz AS (
    SELECT
        m.musteri_id,
        m.musteri_adi,
        COUNT(*) as siparis_sayisi,
        SUM(s.tutar) as toplam_harcama,
        MAX(s.satis_tarihi) as son_alisveris
    FROM musteriler m
    JOIN satislar s ON m.musteri_id = s.musteri_id
    GROUP BY m.musteri_id, m.musteri_adi
)
SELECT
    musteri_adi,
    siparis_sayisi,
    toplam_harcama,
    DATEDIFF(CURRENT_DATE, son_alisveris) as son_alısveristen_gecen_gun
FROM musteri_analiz
WHERE toplam_harcama > 10000
ORDER BY toplam_harcama DESC
LIMIT 10