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Got questions about ClearDB, how it works, or how to use it? We've got answers. Check out the list of common questions and answers below to get started. We also encourage you to become part of the ClearDB community to participate in all things ClearDB, such as getting quick access to support and connecting with ClearDB experts. You can even help shape future product releases from ClearDB!

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General ClearDB Questions

ClearDB Multi-Tenant Database Questions

Common ClearDB Dedicated Cluster Questions

Common ClearDB Billing Questions

Common General ClearDB Answers

What is ClearDB?

ClearDB is a highly available MySQL database-as-a-service that runs in multiple cloud computing as well as in hybrid cloud/datacenter environments. It's designed to eliminate the need to manage your own MySQL database. ClearDB provides specialized, highly available MySQL database clusters that are built around the premise of failure to ensure that your database is always online and fully available, 24/7. We use standard MySQL technology, with a layered software stack "wrapped around" to provide automatic, intelligent support so that you can focus on your application, not managing you database.

What does ClearDB do?

ClearDB provides MySQL database services for your applications in several different environments: in clouds, such as Amazon's EC2 and Windows Azure, on-premise, such as in your data centers and offices, as well as a combination of the two, in our hybrid solutions. You can use ClearDB to store your database information for your application and service workloads.

How does ClearDB work?

ClearDB uses a combination of standard MySQL, mixed in with "master-master" replication as well as our own specialized layered software stack to provide a highly available MySQL database environment for your applications and services. Each cluster is geographically separated to ensure your database's availability, even if an entire network, datacenter, storage, or system failure occurs. Combined with our high availability routing technology, we ensure that your database is always online and fully available, 24/7.

Why should I use ClearDB?

ClearDB is the only real high availability MySQL provider on the market today. Thousands of satisfied customers use our mature, proven software solution and 24/7 customer support to ensure that their database services remain online, no matter what. We're also the only database as a service provider that currently offers an SLA-backed, 100% uptime guarantee. Combined with our solid operations practice, our expert engineers, and our dedicated customer support, you're in good hands with ClearDB.

How does ClearDB compare to Amazon's MySQL RDS?

Amazon's MySQL RDS product provides a "standard MySQL" approach to database availability and performance. With RDS, you can define how many slave systems you would like and assign a single master server. While RDS is an interesting product, it does not solve a number of problems that plague application administrators and developers: how to ensure availability and not get a phone call at 3AM to re-point an application at a different server, or how to ensure that you don't have to worry about things like master elections, or better yet - how to ensure that you don't have to pay a huge amount of money for basic support. Finally, RDS restricts master-slave availability to a single region. Last year alone, a service outage caused an entire EC2 region to become unavailable, causing all of the RDS customers in that region (US-East) to go offline. Here's how ClearDB solves these problems:

  1. We ensure that your applications are never interrupted with our proprietary SQL routing technology. So if a failure occurs, your application will simply continue to run as it should.
  2. Multiple master nodes ensure that things like master elections never interfere with your applications availability.
  3. Our geo-separated configurations ensure that no single region can cause a complete service outage for your applications.
  4. 24/7 customer care and technical support are bundled into our pricing, making ClearDB a much more affordable option than RDS.

ClearDB is 100% dedicated to ensuring the availability, performance, durability and security of your databases, both in-cloud and on-premise. Our service is backed by our 100% uptime SLA, and uses standard, unmodified MySQL to ensure that your applications operate as expected on our database platform. This ensures that you won't be blind-sided by additional cost for having to re-tune your applications. Finally, ClearDB is much more cost effective than Xeround, mainly because our costs are lower than theirs. We didn't re-invent the wheel, we simply put better tires on it.

Does ClearDB work in other environments than Amazon's EC2?

Yes, we do! Our dedicated clusters can operate in the following cloud environments:

  • Amazon's EC2 (Worldwide)
  • Windows Azure (Worldwide)
  • Linode (Worldwide)
  • GoGrid (Worldwide)
  • Rackspace Cloud (Worldwide)

Our multi-tenant database clusters currently operate in the following cloud environments:

  • Amazon's EC2 (US-East, US-West, West Europe)
  • Microsoft's Windows Azure (All regions except South Central US and Southeast Asia)
  • Pivotal.io (US-East)
  • AppFog (US-East)
  • ... more coming soon!

Does ClearDB have any on-premise/hybrid solutions?

Yes, we offer our Hybrid DB configurations, which enable us to provide you with a turn-key VM which can power your database in an on-premise environment, such as local data centers or offices. This on-premise VM connects to your dedicated cluster in the cloud for true, 100% hybrid availability for things like scale-out for seasonal workloads, decision support jobs, etc. Contact us if you would like to know more about our Hybrid DB service offerings.

Does ClearDB offer any data enhancement/data cleaning solutions?

Unfortunately no, we do not. We are focused on providing database services for our customers, and have a strict "hands off" data policy to ensure HIPAA compliance as a data clearinghouse provider.

How does ClearDB scale in comparison to other cloud database services?

ClearDB scales by enabling you to select the type of database plan you would like to use, delivering on highly performant, durable clusters that are properly configured to ensure high performance. Our performance markers are defined by our service plans, or "tiers". Each service tier uses larger resources, larger systems, more storage, more bandwidth, and more power for your database. For our enterprise customers, we offer scalable read pools. Combined with our front and back-end SQL routing technology, we enable your database to function more like a supercomputer, fanning queries out to each read pool, all while ensuring geo-separated, highly available data access.

Multi-tenant ClearDB customers can easily upgrade their database plans to higher multi-tenant plans in-place, without having to migrate data or update their application configurations to point to a different cluster. This makes scaling up easy!

What does ClearDB do if a database server fails?

ClearDB uses intelligent diagnostics technology to assess availability and database node health. In the event that a database node becomes unhealthy or has failed, our SQL routing technology will automatically re-route your connections to the secondary master node to enure that your applications and services remain online and available. In the background, our services will begin diagnosing the failed node. If a problem is identified that can be fixed automatically, our systems will "heal" the failed or unhealthy node and bring it back into service. Once the failed or unhealthy master node has resynchronized with the secondary master, our SQL routing technology will automatically switch back to it. During this process, your applications will never lose access to your database.

Can I lose data if a failure occurs?

In most cases, no. ClearDB uses durable storage (such as EBS on Amazon's EC2, or Azure Drives on Windows Azure) for your databases and MySQL's transaction logs to ensure that your data is available, even if a server instance fails or a storage outage occurs. In the event a server instance fails, we simply spin up a new instance and mount the durable storage from the failed instance onto the new instance and restore cluster services. Upon cluster synchronization, our SQL routing technology will automatically switch back to the failed node (if it has priority).

What is ClearDB's SLA?

Simple. We offer an SLA-backed 100% uptime overall service guarantee on our production services. "Overall service guarantee" means that we guarantee that your database will be available on at least one master node, 100% of the time. See our SLA policy for more details.

What is ClearDB's data jurisdiction policy?

While we do offer support for a trans-atlantic cluster configuration, we also support data jurisdiction for services which require specific region boundaries. They are as follows:

  • Euro Zone: Dublin, London, Amsterdam
  • United States: San Francisco CA, Portland OR, Ashburn VA, Chicago IL, San Antonio TX
  • Pacific Rim: Hong Kong, Singapore, Tokyo

Does ClearDB offer 24/7/365 support?

Yes, we do, and at no additional charge. We're committed to serving your MySQL database needs.

How do I get started with ClearDB?

Sign up for an account with us today!

When I use auto_increment keys (or sequences) in my database, they increment by 10 with varying offsets. Why?

ClearDB uses circular replication to provide master-master MySQL support. As such, certain things such as auto_increment keys (or sequences) must be configured in order for one master not to use the same key as the other, in all cases. We do this by configuring MySQL to skip certain keys, and by enforcing MySQL to use a specific offset for each key used. The reason why we use a value of 10 instead of 2 is for future development.

How do I manage my database(s) on ClearDB? Is there a phpMyAdmin or similar application that I can use?

We recommend that you use MySQL tools, such as the MySQL Workbench or the traditional mysql command line client. You can also use Sequel Pro and other MySQL GUIs to manage your database. For importing data into your MySQL database, we recommend that you use both the mysql command line client as well as the mysqldump database backup utility.

ClearDB Multi-Tenant Database Answers

Where can I get access to ClearDB multi-tenant services?

ClearDB Multi-Tenant database services are available through our Platform-As-A-Service partners:

Do limitations exist on ClearDB's multi-tenant plans vs. ClearDB's dedicated services?

Yes, in order to ensure the highest quality of service for our multi-tenant database customers, we enforce the following SLA policies for multi-tenant services:

  • Maximum Database Connections
  • Maximum Database Size
  • Maximum Queries Per Hour
  • Maximum SELECT Query Execution Time

The values for these SLA policies vary depending on the service plan in use. Larger plans have access to larger amounts of these resources.

How do I know that my database is secure in ClearDB's multi-tenant service?

We utilize best-practice MySQL security enforcement as well as SSL communications security to ensure database security on our multi-tenant clusters, just as we do on our dedicated clusters. We also encrypt all backups on disk to ensure that your data is safe at all times in which it is not inside the database itself.

How fast is ClearDB's multi-tenant service vs. it's dedicated cluster services?

Our multi-tenant database clusters utilize some of the largest instance types in the cloud to ensure high performance and availability for all of our multi-tenant database customers. However, due to the fact that many customers are using our multi-tenant clusters, CPU time and I/O bandwidth must be shared amongst all multi-tenant customers on each cluster. At times, this can potentially reduce the amount of performance that is available per database.

On the other hand, our dedicated clusters provide 100% focused compute resources and bandwidth to your database, 100% of the time. This makes it possible for you to fully utilize the power and capability of an entire database cluster for your applications.

I need more space/power/resources than are available on ClearDB's multi-tenant service plans. What should I do?

We recommend that you sign up for an account with us and purchase a dedicated cluster for your database. This ensures that you get 100% dedicated power and no multi-tenant resource restrictions so that your application can scale as needed.

I need to migrate my data from another provider, such as Heroku Postgres or Xeround into ClearDB. How do I do that?

If you need to migrate your data from another MySQL provider, such as Xeround or Amazon's RDS, simply use the mysqldump utility in conjunction with the mysql command line client. For example:

mysqldump --single-transaction -u (old_database_username) -p -h (old_database_host) (database_name) | mysql -h (cleardb_host) -u (cleardb_user) -p -D (cleardb_database)

You'll be asked for your old database host's password first, then for the password of your new ClearDB database. Once you've authenticated to both hosts, the old database host will simply transfer your database into ClearDB.

If you need to migrate your data from another database provider such as Heroku Postgres, you can use the following methods:

  • Follow Heroku's documentation regarding the use of taps or by using pgbackups to produce a SQL-neutral format that can be imported using the mysql command line client.
  • Use a rake task to migrate your schema only (if that's all you need to migrate)

I suddenly cannot perform INSERT, UPDATE, or CREATE commands on my multi-tenant database. What happened?

This means that you have reached the size limit on your database. This typically happens with our free database plan, where a maximum of 5-10MB is allowed. In order to re-gain write privileges to your database, you'll either need to delete data from it or upgrade your database to a larger plan.

If you are using our largest multi-tenant plan and have reached this point, we recommend that you create an account with us and purchase a dedicated cluster that meets your database needs.

I'm getting an error message saying that I have exceeded the 'max_questions' resource for my database. What can I do?

The max_questions resource is defined by how many queries you may issue to your database in an hour. Our free plans start with 3,600 queries per hour and increase to 18,000 upon purchasing a paid plan with us. Larger plans have larger QPH limits. We recommend that you upgrade your database with us to lift this limitation off of your database.

I received an error message saying that I have exceeded the 'max_user_connections' resource for my database. Why?

Each multi-tenant plan supports a maximum number of database connections that are allowed. This is to ensure the highest quality of service for all of the customers and databases that are on each multi-tenant cluster. If you receive this message, it means that you have reached your connection limit for the plan for which you are currently subscribed. We recommend that you upgrade your database to a larger plan to lift this restriction off of your database.

For some reason some of my longer SELECT queries are being cancelled or killed. What's going on?

In order to maintain the highest quality of service for all of our multi-tenant customers, we limit the amount of execution time allowed for SELECT queries on our multi-tenant clusters. This ensures that no single customer can consume all of the available CPU and I/O resources on the cluster for more than the maximum time allowed. Most of our multi-tenant clusters restrict SELECT query execution time to 60 seconds.

How do I upgrade my current multi-tenant database to a larger plan?

Heroku Customers

If you are interested in upgrading to a larger multi-tenant plan, simply use the heroku addons:upgrade cleardb command to upgrade to the next plan up.

I need help figuring out a problem with my ClearDB multi-tenant database. Who do I need to contact?

First, please check this FAQ for a solution to your problem - the answers you're looking for may already be here! :-)

If you still cannot find a solution to your database problem, please feel free to contact us for assistance.

Common ClearDB Dedicated Cluster Questions

What is the maximum number of connections I can run on a dedicated cluster?

This depends on the size of the cluster being used. The baseline maximum for all of our dedicated clusters is 600 connections. Here's what we currently support:

  • Small DB Dedicated Cluster: 600 connections per node max.
  • Medium DB Dedicated Cluster: 1000 connections per node max.
  • Large DB Dedicated Cluster: 2000 connections per node max.

I need additional security options for my ClearDB cluster. How can I enforce client SSL (or x.509) authentication?

We operate our own CA, and we'll be happy to generate x.509 user authentication certificates for your account. Please send us a support request (login required) to get x.509 certificates.

How long does it take to set up a new cluster for my business?

Currently we hand craft our clusters for dedicated cluster customers. This process typically takes 1-2 business days depending on the cluster type being requested.

Can I order a ClearDB cluster that does not use dual master nodes?

In order to provide the best ClearDB experience possible, we require that all cluster configurations begin with dual master nodes. Our SQL routing technology makes your entire cluster behave more like a single unit so that you don't have to worry about master/slave issues.

My company is interested in using ClearDB, but we have service requirements that are larger than ClearDB's service plans. Can we use ClearDB with a larger configuration than what is listed?

Yes, we do support configurations that are larger than the ones that we list on our website. If you would like to receive a custom quote from us for your database configuration needs, please send our sales team an email with your contact information so that we can begin discussing your database needs as well as set up a demo for your organization.

My business needs a HIPAA-compliant database-as-a-service provider. Is ClearDB HIPAA compliant?

With regards to being a signed business associate serving as a data clearinghouse provider, yes, we are HIPAA compliant with regards to PHA and ePHA protection. We also support safe harbor regulations regarding data jurisdiction. See our data jurisdiction answer for more details.

Why is ClearDB's dedicated cluster pricing different from it's multi-tenant pricing?

ClearDB's dedicated cluster pricing differs from our multi-tenant pricing mainly because of the fact that we're dedicating an entire cluster for you alone. This enables your business to operate using the full power and bandwidth of an whole ClearDB cluster, where our Multi-Tenant customers must share resources on the same cluster.

Common ClearDB Billing Questions

How does ClearDB do billing?

We bill our customers on a monthly basis. Dedicated customers are billed at a standard rate every month. Most of our multi-tenant customers are billed using our partners' pay-per-use billing, which pro-rates their bill. Customers who operate billing through ClearDB are billed at a standard monthly rate.

What billing options are available for dedicated cluster customers?

We support the following billing methods for dedicated customers:

  • Amazon Payments
  • PayPal
  • Wire Transfers (dedicated customers only) with AR/AP

What billing options are available for multi-tenant cluster customers?

Most of our multi-tenant cluster customers' billing operates through our PaaS partners. If you're using one of our multi-tenant clusters with a paid plan, you're already being billed for our services via the PaaS provider you're using.

Why doesn't ClearDB use pay-per-use billing?

It's simple: most of our customers enjoy the fact that they know how much their bill will be at the end of each month, which eases the tension of working with us.

If we need to upgrade our database plan to a larger configuration, how does that affect our billing?

This depends on the larger configuration you're upgrading to. For example, if you're upgrading from one multi-tenant plan to another multi-tenant plan, you will be billed via our PaaS partner's pay-per-use billing process. However, if you're a dedicated cluster customer and want to upgrade to a larger cluster, we will update your payment subscription or create a new subscription for you.