提示在 DB Browser SQLite 中有效但在代码中无效？ ---我的错，解决了

Question

我正在尝试根据价格数据过滤股票列表。老实说，我真的不知道自己在做什么，所以非常感谢您的帮助。我会开门见山的。基本上，这个提示

        select * from (
            select symbol, name, stock_id, max(close), date
            from stock_price join stock on stock.id = stock_price.stock_id
            group by stock_id
            order by symbol
        ) where date = '2021-04-01'

在数据库浏览器 (SQLite) 中运行良好。在应用程序中，我希望它用作过滤器“新收盘高点”：

import sqlite3, config
from fastapi import FastAPI, Request
from fastapi.templating import Jinja2Templates
from datetime import date

app = FastAPI()
templates = Jinja2Templates(directory="templates")

@app.get("/")
def index(request: Request):
    stock_filter = request.query_params.get('filter', False)

    connection = sqlite3.connect(config.DB_FILE)
    connection.row_factory = sqlite3.Row
    cursor = connection.cursor()

    if stock_filter == 'new_closing_highs':
        cursor.execute("""
        select * from (
            select symbol, name, stock_id, max(close), date
            from stock_price join stock on stock.id = stock_price.stock_id
            group by stock_id
            order by symbol
        ) where date = ?
        """, (date.today().isoformat(),))

    else: 
        cursor.execute("""
            SELECT id, symbol, name FROM stock order by symbol
        """)

    rows = cursor.fetchall()

    return templates.TemplateResponse("index.html", {"request": request, "stocks": rows})

@app.get("/stock/{symbol}")
def index(request: Request, symbol):
    connection = sqlite3.connect(config.DB_FILE)
    connection.row_factory = sqlite3.Row
    cursor = connection.cursor()

    cursor.execute("""
        SELECT id, symbol, name FROM stock WHERE symbol = ?
    """, (symbol,))

    row = cursor.fetchall()

    cursor.execute("""
        SELECT *FROM stock_price WHERE stock_ID = ? ORDER BY date DESC
    """, (row['id'],))

    prices = cursor.fetchall()

    return templates.TemplateResponse("stock_detail.html", {"request": request, "stock": row, "bars": prices})

如果过滤器没有在代码中定义，它只会跳回到所有股票，但它会显示一个空的 table，我不明白为什么。运行这与 uvicorn.

到目前为止，数据库有两个 table：股票，包含 Alpaca API:

提供的所有可交易的活跃资产

id  symbol  name                                     Exchange
65  AAA     AAF First Priority CLO Bond ETF          ARCA
66  AAAU    Goldman Sachs Physical Gold ETF Shares   ARCA

和stock_price：

id stock_id    date      open    high    low     close  volume
1   65      2020-10-02  24.9127 24.925  24.9127  24.92  2944
2   65      2020-10-05  24.91   24.94   24.91    24.92  29000
3   65      2020-10-06  24.89   24.91   24.89    24.91  4019
4   65      2020-10-07  24.9017 24.91   24.9     24.91  3800
5   65      2020-10-08  24.9    24.905  24.9     24.9   1534
6   65      2020-10-09  24.88   24.91   24.88    24.89  16273

如果我没有在这里提供足够的信息，请告诉我。非常感谢您抽出时间

Answer 1

我不认为你的查询有效。
也许它恰好适用于您拥有的数据和特定日期 '2021-04-01'.
如果您想获得特定日期每只股票的最高价格，您应该加入表格，按股票分组并汇总：

SELECT s.symbol, s.name, s.id, MAX(p.close) max_price, p.date
FROM stock s INNER JOIN stock_price p
ON p.stock_id = s.id
WHERE p.date = ?
GROUP BY s.symbol, s.name, s.id

Answer 2

我的错！我还没有今天的数据！我以为我做到了，但剧本没有如期运行。应该只是仔细检查一下。很抱歉浪费了你的时间

提示在 DB Browser SQLite 中有效但在代码中无效？ ---我的错，解决了

Prompt works in DB Browser SQLite but not in code? ---my bad, solved

python

sqlite

fastapi