Is there a way how to recover deleted rows in Mysql Database? - mysql

I accidentally deleted records in MSQL database and there is no backup no rollback transaction and i reallly want to recover deleted data back is there any tool to help ? how could i do ? please help me .

Is it MySQL or MSSQL they both are not same. MSSQL stands for SQL Server but by any means for you to recover deleted data either you should have taken a recent full/differential backup in place (or) if you have maintained transaction log. Then yes possible to get back your data by restoring from your backup (or) by reading from transaction log. Else, No there is no way to recover those data.

For InnoDB tables, if binary logs are enabled, one could use:
mysqlbinlog path_to_binary_log_file > query_log.sql
If binary logs are not enabled, there is a recovery tool provided by Percona which may help.
Created a script to automate the steps from the Percona tool which recovers the deleted rows (if exist) and provides SQL queries to load the data back into database.
Please note:
The time between the deletion of rows and the database stop is
crucial. If pages are reused you can’t recover the data.

Related

Recover database using only part of binary log MySql

I have made a backup, then I have executed several statements, including a delete. So I have recovered the backup but I only want to recover the binary log until before the delete operation, what command can I use for this?

how to recover deleted rows from MYSQL database

Today morning I surprisingly found that some data is deleted form my MYSQL database, I am unable to find that data in any table.
Please suggest how to recover data from MySQL database, DOES MYSQL keeps any Log if yes where it is located?
Please suggest any query to get all records.
I am using MYSQL Workbench 5.
If you have binary logs active on your server then you can use mysqlbinlog
You can use the following:
mysqlbinlog binary_log_file > query_log.sql
If you don't have this, then you have probably lost it.
You can look here for more information on how to convert the binary logs to sql.
You can check if binary logging is enabled or not by running the following command:
SHOW VARIABLES LIKE 'log_bin';
For InnoDB tables, if binary logs are not enabled, there is a recovery tool provided by Percona which may help.
Created a script to automate the steps from the Percona tool which recovers the deleted rows (if exist) and provides SQL queries to load the data into database.
Please note:
The time between the deletion of rows and the database stop is
crucial. If pages are reused you can’t recover the data.

Can I recover dropped database in MySQL?

I accidentally dropped a database which I used for my web application, and it is in MySQL. Browsing through the internet I found out that to recover you need to have binary logs enabled. Read that binary logs records only changes in tables, so what it has to do with recovering a db. Upon executing the command "show binary logs;" console shows me "Error Code: 1381. You are not using binary logging". I am a newbie to MySQL, so is it possible to recover it without my binary logging enabled PLUS I have not made any real backup for the db. Going through the MySQL "my.cnf" file found that InnoDB is default enabled, can it help me recover.
If I cannot recover, please mention the steps to be carried out next time creating a new db to ensure that I could recover even if it has been accidentally deleted.
I think it can't be recovered. In case of this case, you can do the following when creating a new db:
open the binary log by add the following:
log-bin=/data/mysqlbinlog/mysql-bin
binlog-format=mixed (or row)
create a slave db.
Good luck for you.

mysql cluster lost data after restore

all,
I use mysqldump to backup mysql cluster data with 10 million lines data daily. Recently, our cluster is crashed after a update, then we restore the .sql file generated by mysqldump. When restoring the database, we got key duplication errors/problem, and then I use "-f" to force the restore process. And finally, the restore process completed and all tables is back. Some tables are smaller, we think that is because the duplicate lines are ignored.
But recently, we find some data is missing, it seems that some duplicated data dose not restored correctly.
May I know whether there is a nice way to avoid this in restore process or how to check whether we have duplication before mysqldump?
Couple of suggestions - take a look at the errors that are generated when not using the force option and see if you can figure out how to fix the root cause. Using the force option allows the restore to continue after the error but the failed rows will still be lost.
Is there a reason why you're using mysqldump rather than the backup command within ndb_mgm - which is an online operation? If using the native Cluster (on-line!) backup then you use the ndb_restore command to restore your data.

mysql replication insert only

I have several slave dbs replicated from the same master db, however, for one of the slaves, i would like to keep it as a backup db, which will never have rows updated or deleted.
basically the purpose is to have a backup db with all rows stored by using the replication(mysqldump is waaay slow to do the backup), no update/delete query get replicated, insert query only. i know there will be some conflicts going on no doubt, but still wonder if any filtering options on statement/query on the slave end or any other solutions.
You should never run a production database without a working backup scheme in place - at least as long as you value your data. If you fear that a wrong sql instruction can ruin your database, then you may try point in time recovery.
If you already use replication your master server will log all write/update operations to its binlog - which it will send to the slave servers for replication. You can do for example nightly backups of you complete database. If you destroy your database in the morning, you can import the backup from the night and reapply the instructions from the binlog from after the backup till before the instruction that killed your database.
You could then skip this instruction and apply the instructions that came afterwards. This can also cause consistency issues, as the instruction after the skipped instruction see different data in the database as they did when they were originally executed.
I have similar problem. I know it's old thread but it can help others:
link: mysql replication works only if I choose database by USE database