* 用例1：获取日内最高价和最低价
```
import dai
df = dai.query("""
SELECT
date, instrument, high, low
FROM cn_stock_real_bar1d
WHERE instrument='000032.SZ'
ORDER BY date""",
filters={"date": ["2023-01-01", "2023-12-31"]}
).df()
```
* 用例2：对比未复权数据和复权数据
```
import dai
df = dai.query("""
SELECT
date, instrument,
t1.open AS real_open,
t1.close AS real_close,
t2.open AS adjust_open,
t2.close AS adjust_close
FROM cn_stock_real_bar1d AS t1
JOIN cn_stock_bar1d AS t2 USING (date, instrument)
WHERE instrument='000032.SZ'
ORDER BY date""",
filters={"date": ["2023-01-01", "2023-12-31"]}
).df()
```
* 用例3：查询特定日期范围内某个证券的最高价和最低价
```
import dai
df = dai.query("""
SELECT
instrument, MAX(high) as max_high, MIN(low) as min_low
FROM cn_stock_real_bar1d
WHERE instrument = '000002.SZ'
GROUP BY instrument""",
filters={"date": ["2023-01-01", "2023-12-31"]}
).df()
```
* 用例4：查询某个日期范围内成交量最大的前10个证券：
```
import dai
df = dai.query("""
SELECT
instrument, SUM(volume) as total_volume
FROM cn_stock_real_bar1d
GROUP BY instrument
ORDER BY total_volume DESC
LIMIT 10""",
filters={"date": ["2023-01-01", "2023-12-31"]}
).df()
```
* 用例5：查询某个日期范围内涨幅最大的前5个证券：
```
import dai
df = dai.query("""
SELECT
instrument, MAX(change_ratio) as max_change_ratio
FROM cn_stock_real_bar1d
GROUP BY instrument
ORDER BY max_change_ratio DESC
LIMIT 5""",
filters={"date": ["2023-01-01", "2023-12-31"]}
).df()
```