Liquibase rollback to tag - liquibase

I am new to Liquibase and I am trying to get the rollback feature working. I am running Liquibase in Windows. I executed an install which tagged the database at version_1.0. I ran an update which tagged the database at version_1.1. Now I am trying to rollback to version_1.0
Here is the command I am running:
liquibase rollback version_1.0
this gives an error that a --changeLogFile is needed so I ran this
liquibase --changeLogFile=v001/master.xml rollback version_1.0
I provide the name of the change log file that was executed during the update, but nothing gets. The update contains 2 create table statements and the tables were not dropped. What am I missing in the rollback process?

Liquibase does not tag the database really. It only tags to know which changessets need to be rolled back.
The rollback will be done by execute the rollback tags in the changeling.

Related

How to use liquibase rollback for drop statements

I am using liquibase version-4.11 connected with snowflake and i have two pipelines for database automation using liquibase one is for DB Deploy and another one is DB Rollback. We are using this pipeline for the schema updation in snowflake. The DB changes has been versioned using tags in DB Deploy Pipeline so the rollback can be achieved using the DB Rollback Pipeline. Whenever i run the rollback pipeline i am facing the below issue for the drop statements :
"Unexpected error running Liquibase: No inverse to liquibase.change.core.DropColumnChange created"
The Liquibase is not supporting the rollback for drop statements. The only way for this is to add the rollback script manually. But in my organization is not possible for adding it manually for all the drop statements. Its there is any ways to achieve the rollback without involving any manual steps?

Liquibase transaction rollback vs <rollback> tag

I learned that Liquibase runs each changeSet in a transaction and commits it after inserting into the DATABASECHANGELOG table.
If something goes wrong during the changeSet, the transaction gets rolled back.
My question is, what happens if the changeSet also includes a <rollback> tag.
I know that the rollback tags are used in combination with liquibase dedicated rollback commands, but which one has precedence during a regular migration, the command from the rollback tag or the transaction abortion?
The <rollback> block is not used in when an update fails. If the update fails, Liquibase just calls "rollback" on the connection and relies on the database to correctly roll things back. The <rollback> block is only used when doing the separate rollback command where we're "undoing" the changeset that was already committed in the database.
NOTE: the fact that Liquibase relies on the connection rollback to revert a failed update is why you have to be careful if you have multiple statements in the same changeSet. If you have two createTable calls and your the database auto-commits after the first and the second fails, the rollback on the connection will not roll back the first table. So when you run update the next time, you'll get a table already exists error from the first createTable. The rules on exactly what statements auto-commit are database-specific, so the good rule of thumb is "only one statement per changeset"

How to rollback my delete data in Postgres after delete operation?

I have not done anything. I just run this command DELETE FROM feed_republic. But I want to get my data again. What should I do?
When I run rollback I am getting the following message. Please help!
WARNING: there is no transaction in progress
I have not used any commit or any other command unlike this question Can I rollback a transaction I've already committed? (data loss).
PostgreSQL is running in autocommit mode, so every statement is running in its own transaction unless you explicitly start a transaction with BEGIN or START TRANSACTION.
The only way you can get your data back is by restoring from a backup.

Rollback tag for DROP table if exist condition

What would be the rollback of droptable:
- changeSet:
id: 1
author: vikas
changes:
- sql:
sql: DROP TABLE IF EXISTS `adapter`
What should I put in rollback for the above changeset.
I am getting below error when I was trying to rollback without having rollback tag:
Error setting up or running Liquibase: liquibase.exception.RollbackImpossibleException: No inverse to liquibase.change.core.RawSQLChange created
The error
Error setting up or running Liquibase: liquibase.exception.RollbackImpossibleException: No inverse to liquibase.change.core.RawSQLChange created
happens because you use raw sql, and not the appropriate tag for it (it would be dropTable), so liquibase doesn't know what to do with it. It can't create a rollback.
Also, the documentation says that
Other refactorings such as “drop table” and “insert data” have no corresponding rollback commands that can be automatically generated. In these cases, and cases where you want to override the default generated rollback commands, you can specify the rollback commands via the tag within the changeSet tag. If you do not want anything done to undo a change in rollback mode, use an empty tag.
So you'll have to create a proper rollback for drop table operation.

How Liquibase rollback when execution failed?

If i run change log file that contain multiple change set from command line and it failed because of wrong sql at say change set 2. So change set 1 has executed and committed then how will i rollback this change using liquibase.
The easiest would be to use the rollbackCount command. Running "liquibase rollbackCount 1" will roll back the last changeSet executed using either the specified <rollback> block in the changeSet or by figuring it out if Liquibaes can based on the information in the changeSet. For example, a createTable command has the information needed to create a drop table statement, but a dropTable command does not have the information needed to do a create table so you would need to specify your own rollback block.