Messages with delayed delivery in an in-database sharded queue

One or more non-transitory computer-readable media storing instructions which, when executed by one or more processors, cause:

• storing a plurality of messages within a sharded message queue maintained by a database management system;
• wherein the sharded message queue comprises a plurality of message queue shards that includes a particular pair of message queue shards;
• wherein the particular pair of message queue shards comprises (a) a non-delay message queue shard, and (b) a delay message queue shard;
• wherein the plurality of messages comprises one or more delayed messages and one or more non-delayed messages;
• wherein storing the plurality of messages comprises:
• storing the one or more delayed messages in the delay message queue shard of the particular pair, and
• storing the one or more non-delayed messages in the non-delay message queue shard of the particular pair;
• making a particular message, from the particular pair of message queue shards, available for dequeuing by:
• identifying a pair of messages comprising a particular delayed message and a particular non-delayed message comprising:
• identifying the particular delayed message, from the delay message queue shard, that is an earliest message from the delay message queue shard that is available for delivery, and
• identifying the particular non-delayed message, from the non-delay message queue shard, that is the earliest message from the non-delay message queue shard that is available for delivery;
• and
• making the particular message of the pair of messages, which has the earliest delivery time of the pair of messages, available for dequeuing.

A system comprising:

• one or more processors;
• wherein the one or more processors are communicatively coupled to storage including one or more non-transitory computer-readable media;
• wherein the one or more non-transitory computer-readable media store instructions which, when executed by the one or more processors, cause:
• storing, on the storage, a plurality of messages within a sharded message queue maintained by a database management system;
• wherein the sharded message queue comprises a plurality of message queue shards that includes a particular pair of message queue shards;
• wherein the particular pair of message queue shards comprises (a) a non-delay message queue shard, and (b) a delay message queue shard;
• wherein the plurality of messages comprises one or more delayed messages and one or more non-delayed messages;
• wherein storing the plurality of messages comprises:
• storing, on the storage, the one or more delayed messages in the delay message queue shard of the particular pair, and
• storing, on the storage, the one or more non-delayed messages in the non-delay message queue shard of the particular pair;
• making a particular message, from the particular pair of message queue shards, available for dequeuing by:
• identifying a pair of messages comprising a particular delayed message and a particular non-delayed message comprising:
• identifying the particular delayed message, from the delay message queue shard, that is the earliest message from the delay message queue shard that is available for delivery, and
• identifying the particular non-delayed message, from the non-delay message queue shard, that is the earliest message from the non-delay message queue shard that is available for delivery;
• and
• making the particular message of the pair of messages, which has the earliest delivery time of the pair of messages, available for dequeuing.