Joining two data tables on a join attribute

A computer system for joining two data tables on a join attribute, the data tables having at least a first and a second attribute, the second attribute being the join attribute, the computer system being configured for:

• providing a function for associating a computing node to a given record based on a value of the first attribute of the given record;
• determining, using the function for each record of the two data tables, the associated computing node;
• distributing the records of the two data tables to the respective determined computing nodes;
• modeling a relationship between the values of the first and second attributes using a predefined dataset;
• re-determining, for the each record of the two data tables, the values of the first attribute using the corresponding values of the second attribute based on the model of the relationship;
• re-determining, using the function for the each record of the two data tables, the associated computing node using the re-determined values of the first attribute;
• and
• for the each record of the two data tables, in response to determining that the re-determined computing node of the each record is different from the node on which the each record is currently distributed, re-distributing the each record to the re-determined computing node.

A computer program product comprising a computer readable storage medium having program instructions embodied therewith, the program instructions executable by a processor to cause the processor to perform a method comprising:

• providing a function for associating a computing node to a given record based on a value of the first attribute of the given record;
• determining, using the function for each record of the two data tables, the associated computing node;
• distributing the records of the two data tables to the respective determined computing nodes;
• modeling a relationship between the values of the first and second attributes using a predefined dataset;
• re-determining, for the each record of the two data tables, the values of the first attribute using the corresponding values of the second attribute based on the model of the relationship;
• re-determining, using the function for the each record of the two data tables, the associated computing node using the re-determined values of the first attribute;
• for the each record of the two data tables, in response to determining that the re-determined computing node of the each record is different from the node on which the each record is currently distributed, re-distributing the each record to the re-determined computing node;
• performing collocated joins of the distributed records and the redistributed record;
• and
• combining results of the collocated joins, thereby resulting in joining the two data tables.