Questions tagged [snapshot]

The processes of creating a point in time copy of data.

Filter by
Sorted by
Tagged with
54
votes
7answers
23k views

Is it possible to quickly create/restore database snapshots with PostgreSQL?

First of all, I'm a developer, not a DBA or sysadmin; please be gentle :) I'm working on an application workflow where a single user action will trigger complex changes in the database - creating ...
15
votes
5answers
2k views

Backing up & restoring 10-20 SQL Server databases to a ~synchronous state?

I need to backup up 10-20 SQL Server 2008 R2 databases with sizes between 10-50 GB, while they are online and used simultaneously by a single enterprise app. I also need to restore them to a state ...
14
votes
2answers
2k views

SQL Server database snapshots for integration testing

I am trying to define a way of working with a test database (in SQL Server) for our integration testing. My idea was to do these steps at the launch of the integration test assembly: create a ...
12
votes
1answer
15k views

How can I query for existing database snapshots in SQL server?

I'm trying to create a t-sql query that can determine whether or not a given database has any database snapshots that were created from it. For example, if I were to create a snapshot like this: ...
11
votes
1answer
4k views

Does SQL Server Snapshot replication completely copy the data every time or does it issue deltas?

I am looking at snapshot replication between two servers. Here is what I have: 500GB database ~500MB nightly bcp loads ~50MB daily transactions I was asking other DBAs in the company about which ...
9
votes
1answer
4k views

EC2 - How to correctly back up PostgreSQL data?

Here is the setup: 1 small Amazon Linux (EBS-backed) EC2 instance with 3 additional volumes. This is both a web server and database server. One volume for code, one for the PostgreSQL (8.4) data ...
9
votes
1answer
5k views

Remote queries at SNAPSHOT isolation level

I'm experimenting with snapshot isolation level. Whenever I try to access a linked server, I get an error: Remote access is not supported for transaction isolation level "SNAPSHOT" I wasn't able ...
8
votes
2answers
1k views

Are SQL Server Database writes slower with Snapshot Isolation?

I have a lot of deadlocks going on in my system. I would like to use Snapshot Isolation to fix them, but my DBA has reserves about it. One of his concerns is that Snapshot Isolation slows down ...
8
votes
2answers
2k views

Advantage of using a database snapshot for reporting purposes

What is the performance advantage of using a snapshot of a database for reporting purposes? The way I see it, it would probably downgrade performance since for every write in the original database, ...
7
votes
3answers
3k views

What methods are available to create a snapshot of an oracle database for testing purposes?

I am new to databases and have just been assigned to work with Oracle. We want to create a snapshot of the database for testing purposes that will allow us to revert back once we're done. I'm a bit ...
6
votes
3answers
1k views

SQL Server 2008 mirrored Database with manual failover, need reporting database

Our current setup is a principal database used in production with a manual failover mirrored database for HA. I need to setup a reporting database as well. What would be the best approach? Shall I ...
6
votes
3answers
3k views

Using SQL Snapshot Replication to refresh TEST databases from PRODUCTION. Why not?

What are the drawbacks and downsides? We want to schedule automatic nightly refreshes of 20 databases, approximately 1GB each, from the PRODUCTION server to the TEST server. We're setting up SQL ...
6
votes
1answer
5k views

What is the proper way to backup MySQL database with rsnapshot?

I want to backup my website that contains both user uploaded images and data stored in MySQL database such that they are always consistent with each other in any particular point of time. While ...
6
votes
2answers
1k views

Sql server snapshot isolation overhead when read_committed_snapshot is enabled

When SQL Server's read committed snapshot is on (and thus some amount of row versioning is necessary), is there any additional overhead caused merely by enabling snapshot isolation? Snapshot ...
6
votes
2answers
40k views

Why is my database stuck in the Restoring state?

I have some unit tests that manipulates data in a database. In order to guarantee that the database state is always the same throughout all the tests, we're trying restore a database snapshot at the ...
6
votes
1answer
206 views

Deploying and rolling back changes in an Availability Group database

I'm looking for a solution or workflow. Here's how I used to do database deploys when using a stand-alone server: Create a snapshot of the production database Deploy changes Verify that the deploy ...
6
votes
1answer
2k views

DB snapshot goes into SUSPECT mode (SQL 2014 on WIN2K8R2)

I was hoping someone here might have encountered this sort of issue and if so what did you do to fix it? Here's some details: DB server: SQL 2014 Enterprise (12.0.4100.1) OS: Windows 2008R2 ...
5
votes
3answers
975 views

Can PostgreSQL support integration test with some kind of throwaway overlay?

It's a common problem to write integration tests that include a database. If the test changes the database then it could effect other tests or the next run of itself. I know that I could wrap my test ...
5
votes
1answer
5k views

How can I determine the date of a snapshot in SQL Server 2008r2?

I am working on implementing an ETL process to load data into a warehouse. Part of this process is pulling data from our production server (Server P) to a staging server where the actual load into ...
5
votes
1answer
3k views

Should snapshot agent continue to run in transactional replication?

We have transactional replication running for a large number of publications on sql server 2008 R2 2 node active/active cluster. I have noticed that the snapshot agent job runs hourly and it looks ...
5
votes
1answer
342 views

Database ID of a non-existent database - time-out waiting for buffer latch on page appearing in error log

Background: I've recently started at a new shop with lots of databases in various states. I arrived this morning (having just been added to the SQL DBA mailing group) to find an email about the ...
4
votes
3answers
602 views

SQL Server - Snapshot is useful in production environments?

I'm reading about SQL Server high availability solutions and disaster recovery and among the available resources the SQL Server have snapshot feature. In theory all seems like beautiful. I also read ...
4
votes
3answers
6k views

How to undo every change made to a database in a controlled environment?

I'm doing system testing of a product, and several tests are severely changing the data of a demo database. The data is quite complex to create queries which will undo the changes done by the tests; ...
4
votes
1answer
637 views

Oracle Materialized View

I need your help with a issue on Oracle Materialized View. I created the Materialized View using the following command: CREATE MATERIALIZED VIEW SNAP_TEST TABLESPACE tbs NOCACHE LOGGING NOPARALLEL ...
4
votes
1answer
242 views

Advice on setting up a Reporting server

I'd like to ask advice on setting up a reporting server please. We have a SQL Server (on a VM) that handles operations. (SQLOps) This primary SQL server instance has a secondary Log Shipping ...
4
votes
1answer
2k views

Why are Stored Procedure schema changes not being replicated when using ”initialize with backup”?

In SQL Server I have set up transational replication using the "initialize with backup" option. Data is being replicated fine, as are schema changes to tables. However, schema changes to stored ...
4
votes
2answers
2k views

Fast backup & restore of MySQL database to revert recent changes

I have a decently big MySQL DB (InnoDB) with size about 400 MB. Thus dumping the whole DB with mysqldump and restoring it back takes forever (more than 15 minutes, which is unacceptable). For ...
3
votes
2answers
3k views

Excessive replication snapshot size causing failure

I am searching for an explanation of a replication snapshot being in excess of 5 times what we're predicting Following a replication failure we are attempting to reinitialise subscriptions with a new ...
3
votes
2answers
4k views

What is the best way to automatically create a snapshot of the table at the certain time?

I have running and quite loaded PostgreSQL server. I need to take snapshots of the certain tables at the certain time (midnight). Those tables are pretty loaded (a lot of updates and inserts). What ...
3
votes
1answer
149 views

Get a listing of snapshot data files

I need to programmatically drop a database with all of its snapshots and then recreate the database and create a new snapshot. I'm having trouble locating where the snapshot files are located from ...
3
votes
1answer
73 views

SQL Server 2016 SP1 + strategy for long term version retention (snapshots, temporal tables, other?)

We have a data mart fed from an upstream data warehouse that we generate reports out of for external parties. I have a business requirement to preserve the state of the database for each month end to ...
3
votes
1answer
292 views

SQL Snapshot Redirect

Company is implementing Database Mirroring Asynchronous with Snapshot. This provides some Disaster Recovery with Reporting area. Server A Principal contains database which mirrors to Server B, ...
3
votes
2answers
1k views

Why database snapshot creation is faster than normal database backups?

Could you tell me any reason why creation of database snapshot is faster than database normal database backups in MS SQL server
3
votes
1answer
164 views

How widespread is the adoption and usage of database snapshots?

After reading up on database snapshots, it seems that they are useful as a backup and quick restore method for small DDL and DML changes. Additionally they are useful for large scale dev/test ...
3
votes
2answers
395 views

Online index rebuild snapshot location and impact of filling index drive

My understanding of a rebuild index online operation is that the index will have a snapshot taken and the rebuild is started on the snapshot index. My question is where does the snapshot index ...
3
votes
1answer
84 views

Questions Concerning Database Snapshots

One of our divisions is running SQL Server 2012 SP1 Enterprise edition for no particular reason (I know, I know... the decision was made before my time and they are resistant to change). What I'm ...
3
votes
1answer
8k views

How to generate replication snapshot without locking tables

When I reinitialize subscription and generate new snapshot it locks all tables and makes the database unusable for a very long time (never waited it out). Is there anyway to do this without locking?
3
votes
1answer
159 views

SQL Server secondary replica snapshot with Basic Availability Group

I have the following scenario: I created an HA group of two nodes in SQL Server 2016 Standard (which is limited to two nodes, one database per group and a non readable secondary replica). I tried to ...
3
votes
1answer
498 views

SQL Server Snapshot Replication and SRDF compatability

Is there anything that breaks down if you use snapshot replication and then use SRDF for disaster recovery (DR) on the snapshot publisher? Specifically I am asking is: On the DR system, would the DR ...
3
votes
3answers
3k views

Snapshot not picking up new articles in SQL Server 2012 transaction replication when added through script

I am trying to add new articles to an existing publication in SQL Server 2012. I am adding the article to the publication with the syntax --add the table into the correct publication sp_addarticle @...
2
votes
3answers
1k views

Where do Database Snapshots store the information what pages have been copied to the snapshot files?

Database snapshot files are sparse files. Only when a page is modified the sparse file is being written to. Reads of the snapshot must be able to know whether the sparse file contains a copied page or ...
2
votes
2answers
2k views

SQL Server: in what situation can snapshot restore be blocked after SET SINGLE_USER?

In my tests, i have the following script: USE master; ALTER DATABASE [TestDB] SET SINGLE_USER WITH ROLLBACK IMMEDIATE RESTORE DATABASE [TestDB] FROM DATABASE_SNAPSHOT = 'TestDBSnapshot' In some case ...
2
votes
1answer
539 views

Would using timestamps solve consistency issues with snapshot isolation?

I'm considering using Snapshot Isolation for some large queries being send from an Access 2007 frontend. These queries are occasionally causing ASYNC_NETWORK_IO waits, and some blocking as well. I'm ...
2
votes
2answers
64 views

Making Production database as Publisher and Distributor for Snasphot Replication

In our environment we are using Log Shipping as DR. Our primary database is a clustered instance. My requirement is to set up a snapshot replication for reporting purposes. My plan is as follows: ...
2
votes
1answer
2k views

Snapshot Backups for SQL Server Databases

We are researching the direction of using Snapshot backups for SQL Server, rather than more traditional backup methods. We are using CommVault (and would be for snapshot too..) I am trying to ...
2
votes
2answers
4k views

Replication Access denied in Replication

I have a database on-prem, and I have an Azure account. I need to establish transactional replication from the on-prem to Azure. First of all I created a publication and after that I made a ...
2
votes
2answers
3k views

SQL Server Transactional replication failed due to snapshot agent failure

I'm trying to set transactional replication between 2 SQL Server 2012 named instances. I've followed a step by step manual and created a Publication. But once I look into Replication Monitor I Get ...
2
votes
1answer
27 views

How does Database Snapshots Work (MySQL)?

I have a MySQL database hosted on an AWS RDS instance. The database has many tables and I observed the following: I picked a table with about 1-2 million records that is indexed on a created_at ...
2
votes
1answer
30 views

SQL Database Snapshot before code depolyment faster than backup

We have code deployments every Thursday, some of the changes involve database changes - before the code is depolyed we do a SQL backup in case there are errors, this usually takes 45 minutes and ...
2
votes
2answers
1k views

Unable to fully drop a database snapshot

I have a job that drops and re-creates a snapshot, it's currently failing when trying to create the database as it says the database already exists. The database however does not have an entry in ...