Created examples for deadlock on each isolation level

read commited/session 1.sql

@@ -0,0 +1,18 @@
+SET TRANSACTION ISOLATION LEVEL READ COMMITTED;
+
+BEGIN TRANSACTION
+    UPDATE Wycieczki
+        SET cena = cena*2
+    WHERE
+        kraj = 'Bangkok'
+-- STEP 1 RUN ABOVE
+
+    SELECT
+        *
+    FROM
+        Bilety
+    WHERE
+        kraj = 'Ateny'
+-- STEP 3 RUN BETWEEN 1 AND 3
+
+COMMIT TRANSACTION 

read commited/session 2.sql

@@ -0,0 +1,18 @@
+SET TRANSACTION ISOLATION LEVEL READ COMMITTED;
+
+BEGIN TRANSACTION
+    UPDATE Bilety
+        SET cena = cena * 2
+    WHERE
+        kraj = 'Ateny'
+-- STEP 2 - RUN ABOVE
+
+    SELECT
+        *
+    FROM
+        Wycieczki 
+    WHERE
+        kraj = 'Bangkok'
+-- STEP 4 RUN BETWEEN 2 AND 4
+
+COMMIT TRANSACTION 

read uncomitted/session 1.sql

@@ -0,0 +1,16 @@
+SET TRANSACTION ISOLATION LEVEL READ UNCOMMITTED;
+
+BEGIN TRANSACTION
+    UPDATE Wycieczki
+        SET cena = 2
+    WHERE
+        kraj = 'Bangkok'
+-- STEP 1 RUN ABOVE
+
+    UPDATE Bilety
+        SET cena = 2
+    WHERE
+        kraj = 'Ateny'
+-- STEP 3 RUN BETWEEN 1 AND 3
+
+COMMIT TRANSACTION 

read uncomitted/session 2.sql

@@ -0,0 +1,16 @@
+SET TRANSACTION ISOLATION LEVEL READ UNCOMMITTED;
+
+BEGIN TRANSACTION
+    UPDATE Bilety
+        SET cena = 1
+    WHERE
+        kraj = 'Ateny'
+-- STEP 2 - RUN ABOVE 
+
+    UPDATE Wycieczki
+        SET cena = 1
+    WHERE
+        kraj = 'Bangkok'
+-- STEP 4 RUN BETWEEN 2 AND 4
+
+COMMIT TRANSACTION 

repeatable read/session 1.sql

@@ -0,0 +1,16 @@
+SET TRANSACTION ISOLATION LEVEL REPEATABLE READ;
+
+BEGIN TRANSACTION T1
+    SELECT
+        SUM(Cena)
+    FROM
+        Wycieczki
+-- STEP 1 RUN ABOVE
+
+    UPDATE Bilety
+        SET cena = cena * 2
+    WHERE
+        kraj = 'Ateny'
+-- STEP 3 RUN BETWEEN 1 AND 3
+
+COMMIT TRANSACTION T1

repeatable read/session 2.sql

@@ -0,0 +1,16 @@
+SET TRANSACTION ISOLATION LEVEL REPEATABLE READ;
+
+BEGIN TRANSACTION T2
+    SELECT
+        SUM(Cena)
+    FROM
+        Bilety
+-- STEP 2 RUN ABOVE
+
+    UPDATE Wycieczki
+        SET cena = cena * 2
+    WHERE
+        kraj = 'Bangkok'
+-- STEP 4 RUN BETWEEN 2 AND 4
+
+COMMIT TRANSACTION T2

serializable/session 1.sql

@@ -0,0 +1,16 @@
+SET TRANSACTION ISOLATION LEVEL SERIALIZABLE;
+
+BEGIN TRANSACTION
+    SELECT
+        SUM(Cena)
+    FROM
+        Wycieczki
+-- STEP 1 RUN ABOVE
+
+    INSERT INTO 
+        Bilety 
+    VALUES
+        (2, 'Honolulu', 1, 2000);
+-- STEP 3 RUN BETWEEN 1 AND 3
+
+COMMIT TRANSACTION

serializable/session 2.sql

@@ -0,0 +1,16 @@
+SET TRANSACTION ISOLATION LEVEL SERIALIZABLE;
+
+BEGIN TRANSACTION
+    SELECT
+        SUM(Cena)
+    FROM
+        Bilety
+-- STEP 2 RUN ABOVE
+
+    INSERT INTO
+        Wycieczki
+    VALUES
+        ('Honolulu', 2000)
+-- STEP 4 RUN BETWEEN 2 AND 4
+
+COMMIT TRANSACTION