vault backup: 2026-07-23 19:06:26
This commit is contained in:
BIN
Binary file not shown.
|
After Width: | Height: | Size: 39 KiB |
BIN
Binary file not shown.
|
After Width: | Height: | Size: 31 KiB |
+23
-1
@@ -93,10 +93,32 @@ Alle benötigten Sperren müssen VOR der ersten Operation auf Daten angefordert
|
||||
- SS2PL = ALLE SPERREN erst NACH Commit/Abort freigeben!!!
|
||||
|
||||
|
||||
## SQL - Isolationsebene
|
||||
### SQL - Isolationsebene
|
||||
![[Pasted image 20260723185542.png]]
|
||||
![[Pasted image 20260723185549.png]]
|
||||
![[Pasted image 20260723185557.png]]
|
||||
|
||||
|
||||
|
||||
## Recovery Grundlagen
|
||||
|
||||
Recovery-relevante Aktion sequentiell append-only auf stabilem Speicher protokollieren!!
|
||||
|
||||
Committed vor dem Crash: REDO subaruuuuuuu
|
||||
Noch aktiv beim Crash: UNDO
|
||||
|
||||
![[Pasted image 20260723185939.png]]
|
||||
|
||||
Das Log muss FRÜHER dauerhaft speichern als Datenbank
|
||||
|
||||
Checkpoints im Log um suche zu verkürzen!
|
||||
|
||||
#### ARIES
|
||||
Algorithm for Recovery and Isolation Exploiting Semantics
|
||||
|
||||
1. Analyse - Scanne ab checkpoint - aktive Transaktionen = loser - REDO start bestimmen
|
||||
2. REDO - Scanne Log - Wende After Images an - Wiederhole auch loser Effekte
|
||||
3. UNDO - Scanne rückwärts nach losern - Updates rückgängig machen - UNDO protokollieren
|
||||
|
||||
|
||||
|
||||
|
||||
+2
@@ -0,0 +1,2 @@
|
||||
![[8-AltDM.pdf]]
|
||||
|
||||
BIN
Binary file not shown.
BIN
Binary file not shown.
+3
@@ -0,0 +1,3 @@
|
||||
![[RDF-combined.pdf]]
|
||||
|
||||
|
||||
Reference in New Issue
Block a user