initialise project

uuid_test.py

@@ -0,0 +1,71 @@
+import sqlite3
+import uuid
+import math
+import time
+
+DB = "uuid_test.db"
+
+# SQLite-Datenbank öffnen/erstellen
+conn = sqlite3.connect(DB)
+cursor = conn.cursor()
+
+cursor.execute("""
+CREATE TABLE IF NOT EXISTS uuids (
+    uuid TEXT PRIMARY KEY
+)
+""")
+conn.commit()
+
+n = 0
+start = time.time()
+
+# UUIDv4 hat 122 zufällige Bits
+N = 2**122
+
+print("UUIDv4-Kollisionstest gestartet!")
+print("Strg+C zum Beenden.\n")
+
+try:
+    while True:
+        new_uuid = str(uuid.uuid4())
+        n += 1
+
+        # Einfügen versuchen
+        try:
+            cursor.execute(
+                "INSERT INTO uuids (uuid) VALUES (?)",
+                (new_uuid,)
+            )
+            conn.commit()
+
+            duplicate = False
+
+        except sqlite3.IntegrityError:
+            # UUID existiert bereits
+            duplicate = True
+
+        # Kollisionswahrscheinlichkeit
+        probability = 1 - math.exp(
+            -(n * (n - 1)) / (2 * N)
+        )
+
+        print(
+            f"\rUUIDs: {n:,} | "
+            f"Letzte: {new_uuid} | "
+            f"Doppelt: {'JA' if duplicate else 'NEIN'} | "
+            f"Kolliw.: {probability:.12e}",
+            end="",
+            flush=True
+        )
+
+        if duplicate:
+            print("\n\n!!! KOLLISION GEFUNDEN !!!")
+            print(f"UUID: {new_uuid}")
+            print(f"Nach {n:,} Versuchen")
+            break
+
+except KeyboardInterrupt:
+    print("\n\nTest beendet.")
+
+finally:
+    conn.close()