Withdata Software provide some ETL (Extract-Transform-Load) tools for PostgreSQL:
FileToDB Load TXT, CSV, TSV, XML, JSON, Excel, SQL, RDF, INI data to PostgreSQL
DBToFile Export PostgreSQL data to TXT, CSV, TSV, XML, JSON, Excel, SQL files
DBCopier Copy data between PostgreSQL and other rational databases
MongoToDB Ease your MongoDB to PostgreSQL converting work
DBBlobEditor Edit / Import / Export BLOB data in PostgreSQL
Convert your data online, free
Free in-browser converters for CSV, Excel, JSON, XML and SQL: Withdata Online Data Conversion. Large files, batch conversion or scheduling? See the offline desktop apps, or browse all data conversion tools.