{"db": "transit", "question": "最近 30 天（按计划发车时间）一趟班次都没跑过的线路有哪些？取消的班次不算跑过。列线路号。", "sql": "SELECT r.route_no FROM routes r WHERE NOT EXISTS (SELECT 1 FROM trips t WHERE t.route_id = r.route_id AND t.status <> '已取消' AND date(t.plan_depart_time) >= date('now', '-30 days'))"}
{"db": "transit", "question": "在岗的司机里，哪些人从来没被投诉过？", "sql": "SELECT d.driver_name FROM drivers d WHERE d.status = '在岗' AND NOT EXISTS (SELECT 1 FROM complaints c WHERE c.driver_id = d.driver_id)"}
{"db": "transit", "question": "有哪些卡坐过车，但一次值都没充过？给卡号和卡类型。", "sql": "SELECT c.card_no, c.card_type FROM cards c WHERE NOT EXISTS (SELECT 1 FROM recharges r WHERE r.card_id = c.card_id) AND EXISTS (SELECT 1 FROM rides x WHERE x.card_id = c.card_id)"}
{"db": "transit", "question": "在用的车里，哪些从来没做过大修？列车牌。", "sql": "SELECT v.plate_no FROM vehicles v WHERE v.status = '在用' AND NOT EXISTS (SELECT 1 FROM maintenance m WHERE m.vehicle_id = v.vehicle_id AND m.maint_type = '大修')"}
{"db": "transit", "question": "哪些司机开过的所有班次（不管什么状态）一起事故都没出过？另外他至少要开完过一趟班次（状态是已完成）。列司机姓名。", "sql": "SELECT d.driver_name FROM drivers d WHERE EXISTS (SELECT 1 FROM trips t WHERE t.driver_id = d.driver_id AND t.status = '已完成') AND NOT EXISTS (SELECT 1 FROM trips t JOIN incidents i ON i.trip_id = t.trip_id WHERE t.driver_id = d.driver_id)"}
{"db": "transit", "question": "只有一条线路经过的站点有哪些？列站名和那条线路的线路号。", "sql": "SELECT s.stop_name, MIN(r.route_no) AS route_no FROM stops s JOIN route_stops rs ON rs.stop_id = s.stop_id JOIN routes r ON r.route_id = rs.route_id GROUP BY s.stop_id HAVING COUNT(DISTINCT rs.route_id) = 1"}
{"db": "transit", "question": "上行、下行两个方向都设了站，但下行站数比上行少的线路有哪些？列线路号、上行站数、下行站数。", "sql": "WITH c AS (SELECT route_id, SUM(direction = '上行') AS up_cnt, SUM(direction = '下行') AS down_cnt FROM route_stops GROUP BY route_id) SELECT r.route_no, c.up_cnt, c.down_cnt FROM c JOIN routes r ON r.route_id = c.route_id WHERE c.up_cnt > 0 AND c.down_cnt > 0 AND c.down_cnt < c.up_cnt"}
{"db": "transit", "question": "有投诉、而且投诉全都还是待处理的线路有哪些？列线路号和投诉条数。", "sql": "SELECT r.route_no, COUNT(*) AS complaint_cnt FROM routes r JOIN complaints c ON c.route_id = r.route_id GROUP BY r.route_id HAVING SUM(c.status <> '待处理') = 0"}
{"db": "transit", "question": "每张卡第一次坐车是哪天？只看坐过车的卡，列卡号和日期。", "sql": "SELECT c.card_no, MIN(date(x.board_time)) AS first_day FROM cards c JOIN rides x ON x.card_id = c.card_id GROUP BY c.card_id"}
{"db": "transit", "question": "每个司机最近一次开完的班次（按计划发车时间）是哪天、跑的哪条线？同一时间有好几趟的，线路都列出来。给司机姓名、日期、线路号。", "sql": "WITH last AS (SELECT driver_id, MAX(plan_depart_time) AS t FROM trips WHERE status = '已完成' GROUP BY driver_id) SELECT d.driver_name, date(l.t) AS last_day, r.route_no FROM last l JOIN trips t ON t.driver_id = l.driver_id AND t.plan_depart_time = l.t AND t.status = '已完成' JOIN drivers d ON d.driver_id = l.driver_id JOIN routes r ON r.route_id = t.route_id"}
{"db": "transit", "question": "每辆车相邻两次保养隔了多少天？只算类型是保养的记录，按开始日期排，同一天的按记录编号；每辆车第一次保养不列。给车牌、这次保养日期、间隔天数。", "sql": "SELECT plate_no, start_date, gap_days FROM (SELECT v.plate_no, m.start_date, julianday(m.start_date) - julianday(LAG(m.start_date) OVER (PARTITION BY m.vehicle_id ORDER BY m.start_date, m.maint_id)) AS gap_days FROM maintenance m JOIN vehicles v ON v.vehicle_id = m.vehicle_id WHERE m.maint_type = '保养') WHERE gap_days IS NOT NULL"}
{"db": "transit", "question": "每个月新办了几张卡，截至当月一共办了多少张？月份写成 YYYY-MM，从早到晚排。", "sql": "SELECT m, cnt, SUM(cnt) OVER (ORDER BY m) AS total_cnt FROM (SELECT strftime('%Y-%m', issue_date) AS m, COUNT(*) AS cnt FROM cards GROUP BY m) ORDER BY m"}
{"db": "transit", "question": "哪些卡第一次充值以后，90 天之内（按日期算，含第 90 天）又充过一次？列卡号。", "sql": "WITH f AS (SELECT card_id, MIN(recharge_time) AS t0 FROM recharges GROUP BY card_id) SELECT c.card_no FROM cards c JOIN f ON f.card_id = c.card_id WHERE EXISTS (SELECT 1 FROM recharges r WHERE r.card_id = f.card_id AND r.recharge_time > f.t0 AND julianday(date(r.recharge_time)) - julianday(date(f.t0)) <= 90)"}
{"db": "transit", "question": "司机入职以后多少天第一次被投诉？按日期相减，只列被投诉过的司机：姓名、天数。", "sql": "SELECT d.driver_name, julianday(date(MIN(c.complaint_time))) - julianday(d.hire_date) AS days FROM drivers d JOIN complaints c ON c.driver_id = d.driver_id GROUP BY d.driver_id"}
{"db": "transit", "question": "最近 60 天每天有多少人次刷卡坐车，比上一个有人刷卡的日子多了多少？按日期从早到晚，第一天的差值空着。", "sql": "SELECT d, cnt, cnt - LAG(cnt) OVER (ORDER BY d) AS diff FROM (SELECT date(board_time) AS d, COUNT(*) AS cnt FROM rides WHERE pay_type = '刷卡' AND date(board_time) >= date('now', '-60 days') GROUP BY d) ORDER BY d"}
{"db": "transit", "question": "哪些卡至少连续两个自然月都充过值？比如 3 月和 4 月都充了就算，3 月和 5 月不算。列卡号。", "sql": "WITH m AS (SELECT DISTINCT card_id, CAST(strftime('%Y', recharge_time) AS INTEGER) * 12 + CAST(strftime('%m', recharge_time) AS INTEGER) AS k FROM recharges), g AS (SELECT card_id, k - ROW_NUMBER() OVER (PARTITION BY card_id ORDER BY k) AS grp FROM m) SELECT c.card_no FROM cards c WHERE c.card_id IN (SELECT card_id FROM g GROUP BY card_id, grp HAVING COUNT(*) >= 2)"}
{"db": "transit", "question": "每条线路最近 90 天跑了多少趟班次、收到多少条投诉？班次按计划发车时间算、不管状态，投诉按投诉时间算。没有的写 0，列线路号、班次数、投诉数。", "sql": "WITH t AS (SELECT route_id, COUNT(*) AS n FROM trips WHERE date(plan_depart_time) >= date('now', '-90 days') GROUP BY route_id), c AS (SELECT route_id, COUNT(*) AS n FROM complaints WHERE date(complaint_time) >= date('now', '-90 days') GROUP BY route_id) SELECT r.route_no, COALESCE(t.n, 0) AS trip_cnt, COALESCE(c.n, 0) AS complaint_cnt FROM routes r LEFT JOIN t ON t.route_id = r.route_id LEFT JOIN c ON c.route_id = r.route_id"}
{"db": "transit", "question": "每辆车的维修保养一共花了多少、开这辆车的班次出事故一共损失多少？两样都没有的车不列，有一样没有的那样写 0。给车牌、维修花费、事故损失。", "sql": "WITH mc AS (SELECT vehicle_id, SUM(cost_amt) AS cost FROM maintenance GROUP BY vehicle_id), lc AS (SELECT t.vehicle_id, SUM(i.loss_amt) AS loss FROM incidents i JOIN trips t ON t.trip_id = i.trip_id GROUP BY t.vehicle_id) SELECT v.plate_no, COALESCE(mc.cost, 0) AS maint_cost, COALESCE(lc.loss, 0) AS incident_loss FROM vehicles v LEFT JOIN mc ON mc.vehicle_id = v.vehicle_id LEFT JOIN lc ON lc.vehicle_id = v.vehicle_id WHERE mc.vehicle_id IS NOT NULL OR lc.vehicle_id IS NOT NULL"}
{"db": "transit", "question": "充过值也坐过车的卡，各充了多少钱、坐车花了多少钱？列卡号、充值总额、乘车总花费，按卡号排。", "sql": "WITH rc AS (SELECT card_id, SUM(amount) AS recharge_total FROM recharges GROUP BY card_id), sp AS (SELECT card_id, SUM(fare_paid) AS spent FROM rides GROUP BY card_id) SELECT c.card_no, rc.recharge_total, sp.spent FROM cards c JOIN rc ON rc.card_id = c.card_id JOIN sp ON sp.card_id = c.card_id ORDER BY c.card_no"}
{"db": "transit", "question": "每个车场有多少辆没报废的车、多少个在岗司机？没有就写 0，列车场名、车辆数、司机数。", "sql": "WITH v AS (SELECT depot_id, COUNT(*) AS n FROM vehicles WHERE status <> '报废' GROUP BY depot_id), d AS (SELECT depot_id, COUNT(*) AS n FROM drivers WHERE status = '在岗' GROUP BY depot_id) SELECT dp.depot_name, COALESCE(v.n, 0) AS vehicle_cnt, COALESCE(d.n, 0) AS driver_cnt FROM depots dp LEFT JOIN v ON v.depot_id = dp.depot_id LEFT JOIN d ON d.depot_id = dp.depot_id"}
{"db": "transit", "question": "每条线路已完成的班次一共拉了多少人次、出了几起事故？只列有已完成班次的线路，没有的数写 0。给线路号、乘车人次、事故数。", "sql": "WITH t AS (SELECT trip_id, route_id FROM trips WHERE status = '已完成'), rc AS (SELECT t.route_id, COUNT(*) AS n FROM rides x JOIN t ON t.trip_id = x.trip_id GROUP BY t.route_id), ic AS (SELECT t.route_id, COUNT(*) AS n FROM incidents i JOIN t ON t.trip_id = i.trip_id GROUP BY t.route_id) SELECT r.route_no, COALESCE(rc.n, 0) AS ride_cnt, COALESCE(ic.n, 0) AS incident_cnt FROM routes r JOIN (SELECT DISTINCT route_id FROM t) tr ON tr.route_id = r.route_id LEFT JOIN rc ON rc.route_id = r.route_id LEFT JOIN ic ON ic.route_id = r.route_id"}
{"db": "transit", "question": "每个司机被投诉的赔付总额，是他开完的班次收到的票款总额的多少倍？票款按乘车记录的实付金额算，两样都有的司机才列：姓名、倍数。", "sql": "WITH comp AS (SELECT driver_id, SUM(compensation_amt) AS c FROM complaints GROUP BY driver_id), fare AS (SELECT t.driver_id, SUM(x.fare_paid) AS f FROM trips t JOIN rides x ON x.trip_id = t.trip_id WHERE t.status = '已完成' GROUP BY t.driver_id) SELECT d.driver_name, comp.c * 1.0 / fare.f AS ratio FROM drivers d JOIN comp ON comp.driver_id = d.driver_id JOIN fare ON fare.driver_id = d.driver_id"}
{"db": "transit", "question": "每个区有几个站点、有几条线路经过？一条线路在区里停好几站也只算一条。列区、站点数、线路数，按区排。", "sql": "WITH s AS (SELECT district, COUNT(*) AS n FROM stops GROUP BY district), r AS (SELECT s.district, COUNT(DISTINCT rs.route_id) AS n FROM stops s JOIN route_stops rs ON rs.stop_id = s.stop_id GROUP BY s.district) SELECT s.district, s.n AS stop_cnt, COALESCE(r.n, 0) AS route_cnt FROM s LEFT JOIN r ON r.district = s.district ORDER BY s.district"}
{"db": "transit", "question": "去年每个车场的车修车花了多少、出事故损失了多少？去年按自然年，修车看开始日期，事故看发生时间。列车场名和两项金额，没有写 0。", "sql": "WITH mc AS (SELECT v.depot_id, SUM(m.cost_amt) AS cost FROM maintenance m JOIN vehicles v ON v.vehicle_id = m.vehicle_id WHERE strftime('%Y', m.start_date) = strftime('%Y', 'now', '-1 year') GROUP BY v.depot_id), lc AS (SELECT v.depot_id, SUM(i.loss_amt) AS loss FROM incidents i JOIN trips t ON t.trip_id = i.trip_id JOIN vehicles v ON v.vehicle_id = t.vehicle_id WHERE strftime('%Y', i.occur_time) = strftime('%Y', 'now', '-1 year') GROUP BY v.depot_id) SELECT d.depot_name, COALESCE(mc.cost, 0) AS maint_cost, COALESCE(lc.loss, 0) AS incident_loss FROM depots d LEFT JOIN mc ON mc.depot_id = d.depot_id LEFT JOIN lc ON lc.depot_id = d.depot_id"}
{"db": "transit", "question": "每个车场开完班次最多的司机是谁？并列的都列。给车场名、司机姓名、班次数。", "sql": "WITH c AS (SELECT d.depot_id, d.driver_name, COUNT(*) AS n FROM drivers d JOIN trips t ON t.driver_id = d.driver_id WHERE t.status = '已完成' GROUP BY d.driver_id), r AS (SELECT *, RANK() OVER (PARTITION BY depot_id ORDER BY n DESC) AS rk FROM c) SELECT dp.depot_name, r.driver_name, r.n FROM r JOIN depots dp ON dp.depot_id = r.depot_id WHERE r.rk = 1"}
{"db": "transit", "question": "每种卡里余额前 3 名的卡，余额一样的名次并列，并列之后的名次往后顺延（比如两张并列第一，下一张就是第三名）。列卡类型、卡号、余额。", "sql": "WITH r AS (SELECT card_type, card_no, balance, RANK() OVER (PARTITION BY card_type ORDER BY balance DESC) AS rk FROM cards) SELECT card_type, card_no, balance FROM r WHERE rk <= 3"}
{"db": "transit", "question": "每条线路上车人数最多的是哪个站？只算刷卡和扫码的，并列的都列。给线路号、站名、人次。", "sql": "WITH c AS (SELECT t.route_id, x.board_stop_id, COUNT(*) AS n FROM rides x JOIN trips t ON t.trip_id = x.trip_id WHERE x.pay_type IN ('刷卡', '扫码') GROUP BY t.route_id, x.board_stop_id), r AS (SELECT *, RANK() OVER (PARTITION BY route_id ORDER BY n DESC) AS rk FROM c) SELECT ro.route_no, s.stop_name, r.n FROM r JOIN routes ro ON ro.route_id = r.route_id JOIN stops s ON s.stop_id = r.board_stop_id WHERE r.rk = 1"}
{"db": "transit", "question": "服务态度和拒载这两类投诉最多的 5 条线路，投诉数一样的按线路 ID 从小到大，只要前 5 条。列线路号和投诉数，按这个顺序排。", "sql": "SELECT r.route_no, COUNT(*) AS n FROM complaints c JOIN routes r ON r.route_id = c.route_id WHERE c.category IN ('服务态度', '拒载') GROUP BY r.route_id ORDER BY n DESC, r.route_id LIMIT 5"}
{"db": "transit", "question": "今年每个车场修车花钱最多的是哪辆车？按维修开始日期算今年，并列都列。给车场名、车牌、今年维修花费。", "sql": "WITH c AS (SELECT v.depot_id, v.plate_no, SUM(m.cost_amt) AS cost FROM maintenance m JOIN vehicles v ON v.vehicle_id = m.vehicle_id WHERE strftime('%Y', m.start_date) = strftime('%Y', 'now') GROUP BY v.vehicle_id) SELECT d.depot_name, c.plate_no, c.cost FROM c JOIN depots d ON d.depot_id = c.depot_id WHERE c.cost = (SELECT MAX(c2.cost) FROM c c2 WHERE c2.depot_id = c.depot_id)"}
{"db": "transit", "question": "每个月（YYYY-MM）损失最大的那起事故出在哪条线路、损失多少？并列都列。", "sql": "WITH x AS (SELECT strftime('%Y-%m', i.occur_time) AS m, r.route_no, i.loss_amt FROM incidents i JOIN trips t ON t.trip_id = i.trip_id JOIN routes r ON r.route_id = t.route_id) SELECT m, route_no, loss_amt FROM x WHERE loss_amt = (SELECT MAX(x2.loss_amt) FROM x x2 WHERE x2.m = x.m)"}
{"db": "transit", "question": "票价最高的三档线路有哪些？票价一样算同一档，比如两条 5 元、三条 3 元、一条 2 元，前三档就是 5、3、2 元这几条。列线路号和票价。", "sql": "WITH r AS (SELECT route_no, fare, DENSE_RANK() OVER (ORDER BY fare DESC) AS dr FROM routes) SELECT route_no, fare FROM r WHERE dr <= 3"}
{"db": "transit", "question": "最近 60 天的严重延误事故，列一下发生时间、线路号、车牌、司机，还有这辆车属于哪个车场。", "sql": "SELECT i.occur_time, r.route_no, v.plate_no, d.driver_name, dp.depot_name FROM incidents i JOIN trips t ON t.trip_id = i.trip_id JOIN routes r ON r.route_id = t.route_id JOIN vehicles v ON v.vehicle_id = t.vehicle_id JOIN drivers d ON d.driver_id = t.driver_id JOIN depots dp ON dp.depot_id = v.depot_id WHERE i.incident_type = '严重延误' AND date(i.occur_time) >= date('now', '-60 days')"}
{"db": "transit", "question": "被投诉的司机，现在固定在哪条线路上？现在固定的线路就是分配记录里还没结束的那条。列投诉编号、司机姓名、线路号，同样的组合只列一次；现在没有固定线路的不列。", "sql": "SELECT DISTINCT c.complaint_id, d.driver_name, r.route_no FROM complaints c JOIN drivers d ON d.driver_id = c.driver_id JOIN driver_assignments a ON a.driver_id = d.driver_id AND a.end_date IS NULL JOIN routes r ON r.route_id = a.route_id"}
{"db": "transit", "question": "坐过夜班线或快线的学生卡、老年卡有哪些？列卡号和持卡人，一张卡只列一次。", "sql": "SELECT DISTINCT c.card_no, c.holder_name FROM rides x JOIN cards c ON c.card_id = x.card_id JOIN trips t ON t.trip_id = x.trip_id JOIN routes r ON r.route_id = t.route_id WHERE c.card_type IN ('学生卡', '老年卡') AND r.route_type IN ('夜班', '快线')"}
{"db": "transit", "question": "每个车场的纯电车最近 30 天跑完了多少趟班次（按计划发车时间）？没跑的车场也列出来写 0。给车场名和趟数。", "sql": "SELECT d.depot_name, COUNT(t.trip_id) AS trip_cnt FROM depots d LEFT JOIN vehicles v ON v.depot_id = d.depot_id AND v.energy_type = '纯电' LEFT JOIN trips t ON t.vehicle_id = v.vehicle_id AND t.status = '已完成' AND date(t.plan_depart_time) >= date('now', '-30 days') GROUP BY d.depot_id"}
{"db": "transit", "question": "哪些站点有 2 条以上（含 2 条）夜班线路经过？列站名和夜班线路数。", "sql": "SELECT s.stop_name, COUNT(DISTINCT r.route_id) AS night_cnt FROM stops s JOIN route_stops rs ON rs.stop_id = s.stop_id JOIN routes r ON r.route_id = rs.route_id WHERE r.route_type = '夜班' GROUP BY s.stop_id HAVING COUNT(DISTINCT r.route_id) >= 2"}
{"db": "transit", "question": "有师傅带的司机，他师傅是哪个车场的？列司机姓名、师傅姓名、师傅所在车场。", "sql": "SELECT d.driver_name, m.driver_name AS mentor_name, dp.depot_name FROM drivers d JOIN drivers m ON m.driver_id = d.mentor_driver_id JOIN depots dp ON dp.depot_id = m.depot_id"}
{"db": "transit", "question": "每条投诉发生那天，被投诉的线路上固定了哪些司机？分配记录的开始日期不晚于投诉那天、结束日期为空或者不早于投诉那天，就算当时固定在这条线上。列投诉编号和司机姓名，同一条投诉同一个司机只列一次。", "sql": "SELECT DISTINCT c.complaint_id, d.driver_name FROM complaints c JOIN driver_assignments a ON a.route_id = c.route_id AND a.start_date <= date(c.complaint_time) AND (a.end_date IS NULL OR a.end_date >= date(c.complaint_time)) JOIN drivers d ON d.driver_id = a.driver_id"}
{"db": "transit", "question": "每条线路开完的班次，平均比计划晚发车几分钟？提前发车算负数。列线路号和平均分钟数。", "sql": "SELECT r.route_no, AVG((julianday(t.actual_depart_time) - julianday(t.plan_depart_time)) * 24 * 60) AS avg_delay_min FROM trips t JOIN routes r ON r.route_id = t.route_id WHERE t.status = '已完成' GROUP BY r.route_id"}
{"db": "transit", "question": "有卡号的乘车记录里，每种卡各占多少比例？给卡类型和占比（0 到 1 的小数）。", "sql": "SELECT c.card_type, COUNT(*) * 1.0 / SUM(COUNT(*)) OVER () AS share FROM rides x JOIN cards c ON c.card_id = x.card_id GROUP BY c.card_type"}
{"db": "transit", "question": "每个车场的车辆完好率是多少？完好率就是在用的车数除以全部车数，报废的也算在全部里。没车的车场不列。", "sql": "SELECT d.depot_name, SUM(v.status = '在用') * 1.0 / COUNT(*) AS good_rate FROM depots d JOIN vehicles v ON v.depot_id = d.depot_id GROUP BY d.depot_id"}
{"db": "transit", "question": "按月看充值金额，每个月比上一个有充值的月份涨了百分之多少？第一个月空着。月份写成 YYYY-MM，按月份排，列月份、充值金额、增长百分比。", "sql": "WITH m AS (SELECT strftime('%Y-%m', recharge_time) AS mon, SUM(amount) AS amt FROM recharges GROUP BY mon) SELECT mon, amt, (amt - LAG(amt) OVER (ORDER BY mon)) * 100.0 / LAG(amt) OVER (ORDER BY mon) AS growth_pct FROM m ORDER BY mon"}
{"db": "transit", "question": "投诉不少于 3 条的线路，结案率各是多少？结案率是已结案的条数除以投诉总条数。按结案率从高到低，一样的按线路 ID 从小到大，列线路号和结案率。", "sql": "SELECT r.route_no, SUM(c.status = '已结案') * 1.0 / COUNT(*) AS close_rate FROM complaints c JOIN routes r ON r.route_id = c.route_id GROUP BY r.route_id HAVING COUNT(*) >= 3 ORDER BY close_rate DESC, r.route_id"}
{"db": "transit", "question": "按总乘车人次给线路分档：一个人都没坐过的叫「零客流」，1 到 2 人次叫「低客流」，3 人次及以上叫「有客流」。每档各有几条线路？", "sql": "WITH c AS (SELECT r.route_id, COUNT(x.ride_id) AS n FROM routes r LEFT JOIN trips t ON t.route_id = r.route_id LEFT JOIN rides x ON x.trip_id = t.trip_id GROUP BY r.route_id) SELECT CASE WHEN n = 0 THEN '零客流' WHEN n <= 2 THEN '低客流' ELSE '有客流' END AS tier, COUNT(*) AS route_cnt FROM c GROUP BY tier"}
{"db": "transit", "question": "每个司机开完的班次，平均一趟拉几个人？没人坐的班次也算一趟。列司机姓名和平均人次。", "sql": "WITH per_trip AS (SELECT t.driver_id, t.trip_id, COUNT(x.ride_id) AS n FROM trips t LEFT JOIN rides x ON x.trip_id = t.trip_id WHERE t.status = '已完成' GROUP BY t.trip_id) SELECT d.driver_name, AVG(p.n) AS avg_riders FROM per_trip p JOIN drivers d ON d.driver_id = p.driver_id GROUP BY d.driver_id"}
{"db": "transit", "question": "每种能源的车，平均每辆修车花多少钱？没修过的车按 0 算进平均里。列能源类型和平均花费。", "sql": "WITH c AS (SELECT v.vehicle_id, v.energy_type, COALESCE(SUM(m.cost_amt), 0) AS cost FROM vehicles v LEFT JOIN maintenance m ON m.vehicle_id = v.vehicle_id GROUP BY v.vehicle_id) SELECT energy_type, AVG(cost) AS avg_cost FROM c GROUP BY energy_type"}
{"db": "transit", "question": "每个月平均一天出几起事故？用当月事故数除以当月的天数（按日历，2 月就按 28 或 29 天）。列月份（YYYY-MM）和日均事故数。", "sql": "WITH m AS (SELECT strftime('%Y-%m', occur_time) AS mon, COUNT(*) AS n FROM incidents GROUP BY mon) SELECT mon, n * 1.0 / (julianday(date(mon || '-01', '+1 month')) - julianday(mon || '-01')) AS per_day FROM m"}
{"db": "transit", "question": "每个司机往上数有几代师傅（师傅的师傅也算）？没有师傅的是 0。列司机姓名和代数。", "sql": "WITH RECURSIVE up(driver_id, mentor_id, depth) AS (SELECT driver_id, mentor_driver_id, 0 FROM drivers UNION ALL SELECT u.driver_id, d.mentor_driver_id, u.depth + 1 FROM up u JOIN drivers d ON d.driver_id = u.mentor_id WHERE u.depth < 50) SELECT d.driver_name, MAX(u.depth) AS generations FROM up u JOIN drivers d ON d.driver_id = u.driver_id GROUP BY u.driver_id"}
{"db": "transit", "question": "把每个司机所有的上辈师傅都列出来（师傅、师傅的师傅……），给司机姓名、师傅姓名、隔了几代，直接带他的师傅算 1 代。", "sql": "WITH RECURSIVE up(driver_id, mentor_id, gen) AS (SELECT driver_id, mentor_driver_id, 1 FROM drivers WHERE mentor_driver_id IS NOT NULL UNION ALL SELECT u.driver_id, d.mentor_driver_id, u.gen + 1 FROM up u JOIN drivers d ON d.driver_id = u.mentor_id WHERE d.mentor_driver_id IS NOT NULL) SELECT a.driver_name, b.driver_name AS mentor_name, u.gen FROM up u JOIN drivers a ON a.driver_id = u.driver_id JOIN drivers b ON b.driver_id = u.mentor_id"}
{"db": "transit", "question": "有没有徒弟比师傅入职还早的？列师傅姓名和徒弟姓名。", "sql": "SELECT m.driver_name AS mentor_name, d.driver_name AS apprentice_name FROM drivers d JOIN drivers m ON m.driver_id = d.mentor_driver_id WHERE d.hire_date < m.hire_date"}
{"db": "transit", "question": "每条线路上行方向的首站和末站是哪两个站？首站是上行顺序号最小的那站，末站是最大的那站，顺序号一样时都取站点 ID 小的。列线路号、首站名、末站名。", "sql": "WITH f AS (SELECT route_id, stop_id, ROW_NUMBER() OVER (PARTITION BY route_id ORDER BY seq_no, stop_id) AS a, ROW_NUMBER() OVER (PARTITION BY route_id ORDER BY seq_no DESC, stop_id) AS b FROM route_stops WHERE direction = '上行') SELECT r.route_no, s1.stop_name AS first_stop, s2.stop_name AS last_stop FROM routes r JOIN f f1 ON f1.route_id = r.route_id AND f1.a = 1 JOIN f f2 ON f2.route_id = r.route_id AND f2.b = 1 JOIN stops s1 ON s1.stop_id = f1.stop_id JOIN stops s2 ON s2.stop_id = f2.stop_id"}
{"db": "transit", "question": "哪些卡在同一个月里坐过两条以上不同的线路？列卡号和月份（YYYY-MM），同一张卡同一个月只列一次。", "sql": "SELECT c.card_no, strftime('%Y-%m', x.board_time) AS ride_month FROM rides x JOIN trips t ON t.trip_id = x.trip_id JOIN cards c ON c.card_id = x.card_id GROUP BY x.card_id, ride_month HAVING COUNT(DISTINCT t.route_id) >= 2"}
{"db": "transit", "question": "哪些卡在乘车记录里一次都没出现过？列卡号。", "sql": "SELECT c.card_no FROM cards c WHERE NOT EXISTS (SELECT 1 FROM rides x WHERE x.card_id = c.card_id)"}
{"db": "transit", "question": "没有卡号的乘车记录有多少条？按支付方式分别数。", "sql": "SELECT pay_type, COUNT(*) AS cnt FROM rides WHERE card_id IS NULL GROUP BY pay_type"}
{"db": "transit", "question": "每条线路一共有多少乘车记录，其中有卡号的有多少？只列有乘车记录的线路，给线路号、总人次、有卡号的人次。", "sql": "SELECT r.route_no, COUNT(*) AS total_cnt, COUNT(x.card_id) AS card_cnt FROM rides x JOIN trips t ON t.trip_id = x.trip_id JOIN routes r ON r.route_id = t.route_id GROUP BY r.route_id"}
{"db": "transit", "question": "每个车场现在有多少辆车不在修？在修是指维修记录里还没结束（结束日期为空）的车。没车的车场也列，写 0。", "sql": "SELECT d.depot_name, COUNT(v.vehicle_id) AS not_in_repair FROM depots d LEFT JOIN vehicles v ON v.depot_id = d.depot_id AND NOT EXISTS (SELECT 1 FROM maintenance m WHERE m.vehicle_id = v.vehicle_id AND m.end_date IS NULL) GROUP BY d.depot_id"}
{"db": "transit", "question": "哪些线路的票价比同一个车场所有线路的平均票价高？列线路号、票价、车场平均票价。", "sql": "SELECT r.route_no, r.fare, a.avg_fare FROM routes r JOIN (SELECT depot_id, AVG(fare) AS avg_fare FROM routes GROUP BY depot_id) a ON a.depot_id = r.depot_id WHERE r.fare > a.avg_fare"}
{"db": "transit", "question": "每个区的站点里，首末站有几个、其他站有几个？列区、首末站数、其他站数。", "sql": "SELECT district, SUM(stop_type = '首末站') AS terminal_cnt, SUM(stop_type <> '首末站') AS other_cnt FROM stops GROUP BY district"}
{"db": "transit", "question": "最近 30 天哪天出的事故最多？并列的几天都列，给日期和事故数。", "sql": "WITH d AS (SELECT date(occur_time) AS day, COUNT(*) AS n FROM incidents WHERE date(occur_time) >= date('now', '-30 days') GROUP BY day) SELECT day, n FROM d WHERE n = (SELECT MAX(n) FROM d)"}
{"db": "transit", "question": "现在挂失的卡有几张？按卡类型分开数。", "sql": "SELECT card_type, COUNT(*) AS cnt FROM cards WHERE status = '挂失' GROUP BY card_type"}
{"db": "transit", "question": "快线都有哪几条？给线路号和票价。", "sql": "SELECT route_no, fare FROM routes WHERE route_type = '快线'"}
{"db": "transit", "question": "西城有哪些枢纽站？", "sql": "SELECT stop_name FROM stops WHERE district = '西城' AND stop_type = '枢纽站'"}
{"db": "transit", "question": "每个车场有几条正在运营的线路？没有的写 0。", "sql": "SELECT d.depot_name, COUNT(r.route_id) AS route_cnt FROM depots d LEFT JOIN routes r ON r.depot_id = d.depot_id AND r.status = '运营' GROUP BY d.depot_id"}
{"db": "transit", "question": "拿老年卡的人里，卡上余额不到 10 块的是谁？给持卡人和余额。", "sql": "SELECT holder_name, balance FROM cards WHERE card_type = '老年卡' AND balance < 10"}