1. A computer-implemented method for identifying transcoding tables in an extract-transform-load (ETL) data integration process, comprising: activating transcoding table detection in the ETL process; identifying, by operation of one or more computer processors, records passing through an operator configured to replace values in the records with values from at least one table linked to the operator before being sent to an output table, wherein the operator specifies an operation for extracting, transforming, or loading data stored in one or more source systems into storage of a target system; adding the at least one table linked to the operator to a list of candidate tables; determining whether each table in the list of candidate tables is a transcoding table by assigning, to each respective table in the list of candidate tables, a score reflecting a greater likelihood that the respective table is a transcoding table upon determining at least one of: that a business term in a business glossary defines the respective table as a transcoding table; that a first concept in a predefined ontology contains semantic values matching values in the respective table; and that an indirect relationship exists between the respective table and a second concept in the ontology; wherein the transcoding table is used to harmonize values from a plurality of tables in the one or more source systems to a table in the target system.