Oracle DB : Export only table data from from all tables of given schemas
Use Datapump (expdp/impdp):
expdp username/password directory=DATAPUMP_DIR schemas=S1,S2,S3 content=DATA_ONLY dumpfile=schema_dump.dmp logfile=export.log

impdp username/password directory=DATAPUMP_DIR dumpfile=schema_dump.dmp logfile=import.log

See here for an excellent reference: https://oracle-base.com/articles/10g/oracle-data-pump-10g
Note: If you export the metadata too (lose the &quot;content=DATA_ONLY&quot; option) then you can have the import process truncate your target tables before reloading them, by specifying the &quot;TABLE_EXISTS_ACTION=TRUNCATE&quot; option.