Table: estonian_badminton_champs
Columns: year
mens_singles
womens_singles
mens_doubles
womens_doubles
mixed_doubles

Question: WHAT ARE THE NAMES OF THE MENS DOUBLES WHEN THE WOMENS DOUBLES WAS PIRET HAMER HELEN REINO?
SQL: SELECT "mens_doubles" FROM estonian_badminton_champs WHERE "womens_doubles" = 'Piret Hamer Helen Reino'

Question: WHAT IS THE NAME OF THE MENS DOUBLES PLAYER WHEN THE WOMENS DOUBLES PLAYER IS HELEN REINO KAI-RIIN SALUSTE?
SQL: SELECT "mens_doubles" FROM estonian_badminton_champs WHERE "womens_doubles" = 'Helen Reino Kai-Riin Saluste'

Question: WHAT IS THE NAME OF THE MIXED DOUBLES PLAYER WHEN THE WOMENS SINGLE PLAYER IS KAIRI VIILUP?
SQL: SELECT "mixed_doubles" FROM estonian_badminton_champs WHERE "womens_singles" = 'Kairi Viilup'

Question: HOW MANY YEARS DID MENS DOUBLES PLAYER HEIKI SORGE MEELIS MAISTE PLAY?
SQL: SELECT COUNT("year") FROM estonian_badminton_champs WHERE "mens_doubles" = 'Heiki Sorge Meelis Maiste'