Abstract: The present disclosure provides methods, systems and apparatus for efficient data management in distributed database system. According to an aspect, a method is provided. The method includes relocating a first table and a second table of a database to a first node of the database, wherein the first table and a second table (or one or more tables which have a colocation relationship with the first table) are associated with one or more distribution keys corresponding to one or more columns of the first table and the second table. The method further includes defining a colocation relationship between the first table and the second table based on a distribution key of the one or more distribution keys. The colocation relationship may indicate that data of the first table and the second table that correspond according to the distribution key are to reside on a same node of the database.

Abstract: A method and system for implementing concurrency control in a database system includes receiving a request from a node for handling by a GTM. Registering the request in a slot in a tracking array where each of the slots represents one of the requests for handling by the GTM. A slot is acquired, and a segment of the tracking array is scanned to determine a batch of pending requests. The batch is used to produce an aggregate request and the aggregate request includes an aggregate increment of a total number of commit requests of the batch. The aggregate request is sent to the GTM using one of a plurality of pre-established connections. A response is received from the GTM that includes a current value of an incremented timestamp. The incremented timestamp is distributed to the requests of the batch and the lock is released.

Abstract: The disclosed systems, structures, and methods are directed towards for processing a lock request by a master node to access a shared data object in a database located at a remote location comprising identifying, in the master node, a category of the lock request. If the lock request is for a self-compatible lock, determining a value of a counter associated with the master node and with one or more other master nodes, and if the value of the counter is zero, locally granting the lock request. If the value of the counter is greater than zero, forwarding the lock request to a global lock manager (GLM), and if the lock request is for a heavy-conflicting lock, forwarding the lock request by the master node to the GLM.