commit 3e696f7d830098c6c1b55116b8d136b48d61e79c
Author: Maksymilian Lúmenn Stachowiak <silmelumenn@gmail.com>
Date:   Mon Dec 11 23:43:31 2023 +0100

    Created examples for deadlock on each isolation level

diff --git a/read commited/session 1.sql b/read commited/session 1.sql
new file mode 100644
index 0000000..b1e015c
--- /dev/null
+++ b/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 
diff --git a/read commited/session 2.sql b/read commited/session 2.sql
new file mode 100644
index 0000000..e90b931
--- /dev/null
+++ b/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 
diff --git a/read uncomitted/session 1.sql b/read uncomitted/session 1.sql
new file mode 100644
index 0000000..acd70f8
--- /dev/null
+++ b/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 
diff --git a/read uncomitted/session 2.sql b/read uncomitted/session 2.sql
new file mode 100644
index 0000000..133efad
--- /dev/null
+++ b/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 
diff --git a/repeatable read/session 1.sql b/repeatable read/session 1.sql
new file mode 100644
index 0000000..69e3319
--- /dev/null
+++ b/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
diff --git a/repeatable read/session 2.sql b/repeatable read/session 2.sql
new file mode 100644
index 0000000..1389300
--- /dev/null
+++ b/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
diff --git a/serializable/session 1.sql b/serializable/session 1.sql
new file mode 100644
index 0000000..1c9128d
--- /dev/null
+++ b/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
diff --git a/serializable/session 2.sql b/serializable/session 2.sql
new file mode 100644
index 0000000..9a7fd52
--- /dev/null
+++ b/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