Operator approach for generic dataflow designs

A computer-readable storage medium storing instructions for generating code that implements a dataflow plan for extracting data from a source database and transforming said data, wherein the instructions, when executed by one or more processors, cause the one or more processors to perform the steps of:

• storing a description of a dataflow that represents the dataflow plan using operators that process data flowing between the operators;
• wherein each operator of the operators defines an operation which has an input rowset and an output rowset;
• wherein the description defines, for each operator of the operators, a structure for the input rowset and a structure for the output rowset;
• making a determination of which particular computer language from a plurality of computer languages in which to generate first code;
• generating the first code in conformance with the particular computer language based on:
• an evaluation of said dataflow plan, and
• the determination of the particular computer language;
• wherein each operator of the operators corresponds to a different portion of the first code.