split or merge shards in a keyspace

Materialize >>

Reshard support horizontal sharding by letting you change the sharding ranges of your existing keyspace.

-cells

optional\

Comma separated Cell(s) or CellAlias(es) to replicate from.

-tablet_types

Source Vitess tablet_type, or comma separated list of tablet types, that should be used for choosing source tablet(s) for the reshard.

Note: If replicating from master, you must explicitly use . If not specified, it defaults to the tablet type(s) specified by the VTTablet command line flag. defaults to replica.

-skip_schema_copy

optional
default false

If true the source schema is copied to the target shards. If false, you need to create the tables before calling reshard.

keyspace.workflow

mandatory

source_shards

mandatory

Comma separated shard names to reshard from.

target_shards

mandatory

Comma separated shard names to reshard to.

Once you decide on the new resharding strategy for a keyspace, you need to initiate a VReplication workflow as follows:

1. Monitor the workflow using or VExec
2. Confirm that data has been copied over correctly using
3. Start the cutover by routing all reads from your application to those tables using SwitchReads
4. Complete the cutover by routing all writes using