1. A computer-implemented method for generating code corresponding to a splitter operation in an extract, transform, and load (ETL) process, the method comprising: receiving a data flow including a splitter operation, a splitter operation being an operation that places rows from a single input data set into a plurality of output data sets according to a pre-determined condition; and generating an execution plan graph based on the data flow, the execution plan graph including structured query language (SQL) code for implementing the splitter operation, wherein the structured query language (SQL) code is respectively executable among database servers associated with different vendors.