1. A computer-implemented method to identify reference data tables in an extract-transform-load (ETL) data integration process including at least a database field, the computer-implemented method comprising: identifying a first reference data operator in the ETL data integration process, wherein the first reference data operator references one or more tables; computing a score for a first of the one or more tables referenced by the first reference data operator, by operation of one or more computer processors, wherein the score reflects a degree to which the first table has one or more aspects resembling one or more predefined aspects of a reference data table that enumerates a set of possible values that the database field is permitted to contain, wherein the score for the first table is computed based on the one or more aspects of the first table, wherein the one or more aspects are selected from: (i) a column count of the first table; (ii) a row count ratio between the first table to a given table having a greatest row count in a domain; (iii) a column count ratio between the first table to a given table having a greatest column count in the domain; (iv) a first business term, in a business glossary, defining the first table as a reference data table; (v) a match percentage between values in the first table and semantic values in a first concept in a predefined ontology; and (vi) a path length between two concept nodes in an ontology graph; upon determining that the score computed for the first table exceeds a predefined threshold score, designating the first table as a reference data table; and responsive to a request specifying data desired to be transformed, transforming the specified data based on a transcoding table harmonizing a plurality of reference data tables including the first table.