CREATE TABLE labevents (row_id NUMBER, subject_id NUMBER, hadm_id NUMBER, itemid NUMBER, charttime TIME, valuenum NUMBER, valueuom CLOB)
CREATE TABLE procedures_icd (row_id NUMBER, subject_id NUMBER, hadm_id NUMBER, icd9_code CLOB, charttime TIME)
CREATE TABLE d_labitems (row_id NUMBER, itemid NUMBER, label CLOB)
CREATE TABLE cost (row_id NUMBER, subject_id NUMBER, hadm_id NUMBER, event_type CLOB, event_id NUMBER, chargetime TIME, cost NUMBER)
CREATE TABLE d_icd_diagnoses (row_id NUMBER, icd9_code CLOB, short_title CLOB, long_title CLOB)
CREATE TABLE diagnoses_icd (row_id NUMBER, subject_id NUMBER, hadm_id NUMBER, icd9_code CLOB, charttime TIME)
CREATE TABLE prescriptions (row_id NUMBER, subject_id NUMBER, hadm_id NUMBER, startdate TIME, enddate TIME, drug CLOB, dose_val_rx CLOB, dose_unit_rx CLOB, route CLOB)
CREATE TABLE d_icd_procedures (row_id NUMBER, icd9_code CLOB, short_title CLOB, long_title CLOB)
CREATE TABLE outputevents (row_id NUMBER, subject_id NUMBER, hadm_id NUMBER, icustay_id NUMBER, charttime TIME, itemid NUMBER, value NUMBER)
CREATE TABLE inputevents_cv (row_id NUMBER, subject_id NUMBER, hadm_id NUMBER, icustay_id NUMBER, charttime TIME, itemid NUMBER, amount NUMBER)
CREATE TABLE chartevents (row_id NUMBER, subject_id NUMBER, hadm_id NUMBER, icustay_id NUMBER, itemid NUMBER, charttime TIME, valuenum NUMBER, valueuom CLOB)
CREATE TABLE d_items (row_id NUMBER, itemid NUMBER, label CLOB, linksto CLOB)
CREATE TABLE microbiologyevents (row_id NUMBER, subject_id NUMBER, hadm_id NUMBER, charttime TIME, spec_type_desc CLOB, org_name CLOB)
CREATE TABLE patients (row_id NUMBER, subject_id NUMBER, gender CLOB, dob TIME, dod TIME)
CREATE TABLE transfers (row_id NUMBER, subject_id NUMBER, hadm_id NUMBER, icustay_id NUMBER, eventtype CLOB, careunit CLOB, wardid NUMBER, intime TIME, outtime TIME)
CREATE TABLE icustays (row_id NUMBER, subject_id NUMBER, hadm_id NUMBER, icustay_id NUMBER, first_careunit CLOB, last_careunit CLOB, first_wardid NUMBER, last_wardid NUMBER, intime TIME, outtime TIME)
CREATE TABLE admissions (row_id NUMBER, subject_id NUMBER, hadm_id NUMBER, admittime TIME, dischtime TIME, admission_type CLOB, admission_location CLOB, discharge_location CLOB, insurance CLOB, language CLOB, marital_status CLOB, ethnicity CLOB, age NUMBER)

what was the three most frequently done surgeries for patients 20s?
SELECT d_icd_procedures.short_title FROM d_icd_procedures WHERE d_icd_procedures.icd9_code IN (SELECT t1.icd9_code FROM (SELECT procedures_icd.icd9_code, DENSE_RANK() OVER (ORDER BY COUNT(*) DESC) AS c1 FROM procedures_icd WHERE procedures_icd.hadm_id IN (SELECT admissions.hadm_id FROM admissions WHERE admissions.age BETWEEN 20 AND 29) GROUP BY procedures_icd.icd9_code) AS t1 WHERE t1.c1 <= 3)
WITH "_u_0" AS (SELECT "admissions"."hadm_id" FROM "admissions" WHERE "admissions"."age" <= 29 AND "admissions"."age" >= 20 GROUP BY "hadm_id"), "t1" AS (SELECT "procedures_icd"."icd9_code", DENSE_RANK() OVER (ORDER BY COUNT(*) DESC) AS "c1" FROM "procedures_icd" LEFT JOIN "_u_0" "_u_0" ON "_u_0"."" = "procedures_icd"."hadm_id" WHERE NOT "_u_0"."" IS NULL GROUP BY "procedures_icd"."icd9_code"), "_u_1" AS (SELECT "t1"."icd9_code" FROM "t1" "t1" WHERE "t1"."c1" <= 3 GROUP BY "icd9_code") SELECT "d_icd_procedures"."short_title" FROM "d_icd_procedures" LEFT JOIN "_u_1" "_u_1" ON "_u_1"."" = "d_icd_procedures"."icd9_code" WHERE NOT "_u_1"."" IS NULL