CREATE TABLE table_name_26 (ipsos_5_25_09 VARCHAR2, tns_sofres_5_28_09 VARCHAR2)

Which Ipsos 5/25/09 has a TNS-Sofres 5/28/09 of 20%?
SELECT ipsos_5_25_09 FROM table_name_26 WHERE tns_sofres_5_28_09 = "20%"
SELECT "ipsos_5_25_09" FROM "table_name_26" WHERE "20%" = "tns_sofres_5_28_09"