Composite hash and list partitioning of database tables

A data storage system for storing rows of data in a data table, comprising:

• a server running a storage engine including a partitioning module;
• a set of original data nodes managed by the storage engine;
• and
• the data table of data horizontally partitioned with a partition with a set of rows in each of the original data nodes, wherein the storage engine operates the partitioning module to generate a distribution mapping defining a new partitioning of the data table when a new data node is added to the set of original data nodes, the distribution mapping providing uniform distribution of rows of the data across partitions in the new partitioning and retaining a subset of the rows of the data in each of the original ones of the original data nodes,
• wherein the partitioning module comprises a partition function that combines hash and list partitioning to create the distribution mapping.

A data storage system for storing rows of data in a table, comprising:

• a server running a storage engine including a partitioning module;
• a set of original data nodes managed by the storage engine;
• and
• a table of data horizontally partitioned with a partition with a set of rows in each of the original data nodes,
• wherein the storage engine operates the partitioning module to generate a distribution mapping defining a new partitioning of the data table when a new data node is added to the set of original data nodes, the distribution mapping providing uniform distribution of rows of the data across partitions in the new partitioning and retaining a subset of the rows of the data in each of the original ones of the original data nodes, and
• wherein the partitioning module includes modulo hash partitioning as a function of elements in the data table.

A computer program product including a computer useable medium with computer readable code embodied on the computer useable medium, the computer readable code comprising:

• computer readable program code devices configured to cause a computer to add a node to a data storage cluster, wherein the data storage cluster stores a table of data in a horizontally partitioned manner over a number of nodes according to a first distribution mapping;
• computer readable program code devices configured to cause the computer to create a second distribution mapping defining partitioning of the table of data including an additional partition in the added node;
• computer readable program code devices configured to cause the computer to copy one or more rows associated with the table of data from the number of nodes to the added node, the copied rows being defined by the second distribution mapping and the copying excluding copying between the number of nodes, whereby data is retained on the number of nodes and
• computer readable program code devices configured to cause the computer to effect deleting the copied rows from the number of nodes, whereby data is retained on the number of nodes except data in the copied rows.

A computer program product including a computer useable medium with computer readable code embodied on the computer useable medium, the computer readable code comprising:

• computer readable program code devices configured to cause a computer to add a node to a data storage cluster, wherein the data storage cluster stores a table of data in a horizontally partitioned manner over a number of nodes according to a first distribution mapping;
• computer readable program code devices configured to cause the computer to create a second distribution mapping defining partitioning of the table of data including an additional partition in the added node;
• computer readable program code devices configured to cause the computer to copy one or more rows associated with the table of data from the number of nodes to the added node, the copied rows being defined by the second distribution mapping and the copying excluding copying between the number of nodes, whereby data is retained on the number of nodes;
• and
• computer readable program code devices configured to cause the computer to delete the copied rows from the number of nodes after switching distribution to the second distribution mapping and waiting for scans to the number of nodes based on the first distribution mapping to complete.

A computer program product including a computer useable medium with computer readable code embodied on the computer useable medium, the computer readable code comprising:

• computer readable program code devices configured to cause a computer to add a node to a data storage cluster, wherein the data storage cluster stores a table of data in a horizontally partitioned manner over a number of nodes according to a first distribution mapping;
• computer readable program code devices configured to cause the computer to create a second distribution mapping defining partitioning of the table of data including an additional partition in the added node;
• computer readable program code devices configured to cause the computer to copy one or more rows associated with the table of data from the number of nodes to the added node, the copied rows being defined by the second distribution mapping and the copying excluding copying between the number of nodes, whereby data is retained on the number of nodes;
• and
• computer readable program code devices configured to cause the computer to create reorganization triggers transferring data manipulation language (dml) from partitions based on the first distribution mapping to partitions based on the second distribution mapping and, after the copying, commit to transactions to the table of data stored in the data storage cluster.