SERVER-6095 make multikey indices useful for sharding

• 
• Closed

SERVER-6493 Inserting array value for non-shard-key field used in prefix shard key index succeeds

• 
• Closed

SERVER-6809 splitVector doesn't filter additional index fields when shard key is prefix of index

• 
• Closed

DOCS-247 Changing Shard Key Index; shard key index can be a compound index using the shard key as the prefix

• 
• Closed

SERVER-6107 Add more tests for sharding operations with prefix shard key

• 
• Closed