CLIENT CONNECTION ROUTING IN SHARDED DATABASE ENVIRONMENT

(Doc ID 2385973.1)

Last updated on APRIL 13, 2018

Applies to:

Oracle Database - Enterprise Edition - Version 12.2.0.1 and later
Information in this document applies to any platform.

Goal

Oracle Sharding supports two types of routing.

The following topics describe routing in an SDB environment.

Direct Routing to a Shard:
Oracle clients and connections pools are able to recognize sharding keys specified in the connection string for high performance data dependent routing. A shard routing cache in the connection layer is used to route database requests directly to the shard where the data resides.

Queries and DMLs via Proxy Routing in an SDB:
Sharding supports routing for queries that do not specify a sharding key. This allows the flexibility for any database application to execute SQL statements (including SELECT and DML) in a system where tables are sharded or duplicated without the need to specify the shards where the query should be executed.

We will discuss below two methods to connect to sharded database.

1- Connect to a shard by specifying a sharding_key
2- Connect to the shardcatalog via GDS$CATALOG service

Solution

Sign In with your My Oracle Support account

Don't have a My Oracle Support account? Click to get started

My Oracle Support provides customers with access to over a
Million Knowledge Articles and hundreds of Community platforms