CREATE TABLE table_52031 ("Player" TEXT, "Nationality" TEXT, "Position" TEXT, "Years for Jazz" TEXT, "School/Club Team" TEXT)

Who is the center position of Years for Jazz, Greg Ostertag?
SELECT "Years for Jazz" FROM table_52031 WHERE "Position" = 'center' AND "Player" = 'greg ostertag'
SELECT "Years for Jazz" FROM "table_52031" WHERE "Player" = 'greg ostertag' AND "Position" = 'center'