CREATE TABLE table_train_210 ("id" NUMBER, "serum_potassium" FLOAT, "serum_calcium" FLOAT, "estimated_glomerular_filtration_rate_egfr" NUMBER, "body_mass_index_bmi" FLOAT, "age" FLOAT, "NOUSE" FLOAT)

serum potassium < 3.5 mmol / l
SELECT * FROM table_train_210 WHERE serum_potassium < 3.5
SELECT * FROM "table_train_210" WHERE "serum_potassium" < 3.5