- Scale out using tens, hundreds or thousands of database nodes using commodity hardware instead of expensive scale-up systems,
- To achieve scalable performance as the number of nodes increases,
- Build a solution with an excellent price-performance ratio derived from the use of commodity hardware instead of expensive application servers
- SQL Database provides a high availability SLA of 99.9% for all databases, no need to implement RAID and other availability techniques yourself.
- Every table must have a primary key.
- Sharded key must be a primary key or part of primary key in related tables (Clustered index required).
- Identity and Timestamp are not included as a part of data types for sharded tables
- Identity can be set in Root DB tables and Sharding reference tables. (both terms defined during step by step creation)
- Root DB collation and size are replicated to all sharded databases.
- You need to manage schema changes in all databases manually to avoid merging problems.
- Replication not support with table scripts.
- Need to mention Federation key at table creation level even root database are not created yet (using this tool).
- Federated On is keyword to add this table into federation
- "UserId" is key attribute on which we need to generated shards.
- "= UserId" is the Key column that has data and on the basis of this data definition shards data will be moved from one to other federation.
Use "Connect to Server" and by providing Azure credentials as we can see in next screen shot you will be connected to Azure Database server.
As there is no database created yet. We need a database or Root database to start our database migration.
Click on Create Database and You can et its size and Edition along with its name.
Following editions are available
- Express -- Web Editions
- Workgroup -- Business Editions
You can connect and query your database from Online Management Studio and Local management studio as well.
Merging Federated Members
- For merging you need to remember
- All data of deleting member will be lost
- Take backup of both members (merger and deleting)
- After merging member you need to insert all deleted member data manually
- If you delete Federation all members will be lost
- You need to make your federation members offline to avoid problems to your customer
- How to Query a specific Shard.
- How to Check database usage size.
- How to View your sharding database ranges and Stats by Query.
- Querying your database using Online and On-premises database management studio.