CREATE TABLE finrev_fed_17 (state_code NUMBER, idcensus NUMBER, school_district CLOB, nces_id CLOB, yr_data NUMBER, t_fed_rev NUMBER, c14 NUMBER, c25 NUMBER)
CREATE TABLE finrev_fed_key_17 (state_code NUMBER, state CLOB)
CREATE TABLE ndecoreexcel_math_grade8 (year NUMBER, state CLOB, all_students CLOB, average_scale_score NUMBER)

How many unique school districts in Indiana?
SELECT COUNT(DISTINCT school_district) FROM finrev_fed_17 AS T1 JOIN finrev_fed_key_17 AS T2 ON T1.state_code = T2.state_code WHERE T2.state = "Indiana"
SELECT COUNT(DISTINCT "school_district") FROM "finrev_fed_17" "T1" JOIN "finrev_fed_key_17" "T2" ON "Indiana" = "T2"."state" AND "T1"."state_code" = "T2"."state_code"