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Sharded tables

To detect (and route) sharded queries, PgDog expects the sharded column, and optionally, the tables, to be specified in the configuration. For example:

[[sharded_tables]]
database = "prod"
table = "users"
column = "id"
data_type = "bigint"

All queries that reference the "users"."id" column will be routed to the correct shard(s) automatically.

If a column is a foreign key, you can specify just the column name, as long as it's uniquely named. For example:

[[sharded_tables]]
database = "prod"
column = "user_id"
data_type = "bigint"

All queries that reference the "user_id" column in any table will be sharded and routed to the right shard(s).

Data types

Currently, PgDog supports sharding BIGINT (and BIGSERIAL) and UUID. The data type for each table/column must be specified so PgDog can correctly decode it at runtime.

database

Name of the database in [[databases]] section the sharded table belongs to.

table

Name of the sharded PostgreSQL table. Must not contain the schema name, just the table name. Identical table names in multiple schemas are not supported (yet).

column

Name of the sharded column.

data_type

The data type of the column. Currently, the options are:

  • bigint
  • uuid