Techniques are disclosed for identifying transcoding tables in an Extract-Transform-Load (ETL) process, by 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 by a target system, and evaluating at least a first table linked to the operator to determine whether the first table is a transcoding table by assigning a score to the first table, wherein the score is indicative of the likelihood that the first table is a transcoding table, wherein a 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.