Skip to main content
Search type Search syntax
Tags [tag]
Exact "words here"
Author user:1234
user:me (yours)
Score score:3 (3+)
score:0 (none)
Answers answers:3 (3+)
answers:0 (none)
isaccepted:yes
hasaccepted:no
inquestion:1234
Views views:250
Code code:"if (foo != bar)"
Sections title:apples
body:"apples oranges"
URL url:"*.example.com"
Saves in:saves
Status closed:yes
duplicate:no
migrated:no
wiki:no
Types is:question
is:answer
Exclude -[tag]
-apples
For more details on advanced search visit our help page
Results tagged with
Search options not deleted user 69194

Transaction log is a list/history of modification executed by a database management system to guarantee ACID properties over crashes or hardware failures.

0 votes
0 answers
20 views

InnoDB: does `redo log` contain initial value and final value? or just final value?

start transaction; update users set age = 34 where user_id = 3 // update age from 30 to 34 years old. .... .... when I am updating the age of this user, InnDB will write redo log. What's the stru …
Ryan Lyu's user avatar
  • 523
1 vote
3 answers
683 views

InnoDB: will uncommitted transaction produce redo log?

Before MySQL commit a transaction, it will write REDO log first, then commit the transaction, that is write ahead log. start transaction; update users set uuid = UUID() from user where id = 1 update …
Ryan Lyu's user avatar
  • 523
1 vote
Accepted

InnoDB: will uncommitted transaction produce redo log?

Based on Jeremy Cole's presentation InnoDB: A journey to the core III in Percona Live MySQL Conference 2015. When the transaction is first started: A transaction ID (TRX_ID) is assigned and may be …
Ryan Lyu's user avatar
  • 523
1 vote
0 answers
599 views

MySQL: why undo log is required in the processes of database recovery?

Let's imagine that an incident happens when you updates. start transaction; update users set gender = 1 where id = 3; Undo log space is allocated. Previous values are copied to undo log Record of …
Ryan Lyu's user avatar
  • 523