从 SQL 结果中获取数据

Question

有人可以帮我理解如何选择在 sql RESULT 中显示的字段值吗？我想使用该值来运行新的不同查询。

我正在使用 Python 连接 html、apache 和 sql server 来创建一个将运行 SQL 查询并显示结果的网站。一旦我得到结果，我想在新的 SQL 查询中使用一列的值。有没有办法做到这一点，而不是在表单中手动输入值？

代码 1：下面的代码执行数据库调用，根据 sql 查询显示结果。

# prepare a cursor object using cursor() method
cursor = db1.cursor()

SQLQuery = ("SELECT  I.OpinionID,
                     I.TimeStamp,
                     I.Strategy,
                     I.ExpectedTradingPrice,
                     I.ExpectedDate,
                     I.CPAMAnalyst,
                     I.Conviction,
                     I.Status,
                     N.DebtTicker,
                     N.InstrumentType,
                     N.ExpectedMaturity,
                     N.OrderSize,
                     N.Allocation
                 From [CpamTestAugustTestSteve].[dbo].[NewIssueOpinion] I
                 INNER JOIN [CpamTestAugustTestSteve].[dbo].[NewIssue] N ON I.NewIssueID = N.NewIssueID
                 WHERE N.ExpectedIssueDate >= GetDate()-30
                     AND I.Status = 'Suggested' AND I.Active = 1;")

#Execute the SQL command
cursor.execute(SQLQuery)


#Fetch all the rows in a list of lists.
results=cursor.fetchall()
y = len(results)


print "<br> <br>"
print "<body2>"
print """<form action="http://localhost/NewIssueStatusUpdate.py" method="post">
            <div> <input type="Submit" class= "submitbutton" value="Submit" /> </div> <br> <br>
</form>"""
if  not cursor.rowcount:
    print "<b> <mark> NO RECORDS FOUND!!</mark> </b>"
else:
    print "<TABLE>"
    print "<tablebody>"
    print"<tr>"
    print "<tr><th>S.No</th><th>OpinionID</th> <th>TimeStamp</th> <th>Strategy</th> <th>ExpectedTradingPrice</th> <th>ExpectedDate</th> <th>CPAMAnalyst</th> <th>Conviction</th> <th>Status</th> <th>DebtTicker</th> <th>InstrumentType</th> <th>ExpectedMaturity</th> <th>OrderSize</th> <th>Allocation</th><th>New Status</th>"
    for p in range(y):
        print "<tr><td>%s</td>" %(p+1)
        for q in range(len(results[p])):
            r= results[p][q]   
            print "<td> %s </td>" % (r)
    print "<td><select id='statusSelect' onchange='myChangeHandler(this)'><option value='Suggested'>Select</option><option value='accept'>Accept</option><option value='reject'>Reject</option><option value='terminated'>Terminated</option></select></td>"
    print "</TABLE>"
    from tabulate import tabulate

我在“新状态”上方的结果中添加了一个自定义列，我们可以在其中选择要分配给记录的新状态。

我想写一个可以用来更新数据库的代码。查询是：

"UPDATE NewIssueOpinion " & _
"SET Status = '" & Status & "' " & _ #Getting Status using getformvalue.
"WHERE OpinionID = " & OpinionID & ";"     #How can we select the Opinion ID value from the result displayed from code1.

更新代码：

# prepare a cursor object using cursor() method
cursor = db1.cursor()

SQLQuery = ("SELECT  I.OpinionID,
                     I.TimeStamp,
                     I.Strategy,
                     I.ExpectedTradingPrice,
                     I.ExpectedDate,
                     I.CPAMAnalyst,
                     I.Conviction,
                     I.Status,
                     N.DebtTicker,
                     N.InstrumentType,
                     N.ExpectedMaturity,
                     N.OrderSize,
                     N.Allocation
                 From [CpamTestAugustTestSteve].[dbo].[NewIssueOpinion] I
                 INNER JOIN [CpamTestAugustTestSteve].[dbo].[NewIssue] N ON I.NewIssueID = N.NewIssueID
                 WHERE N.ExpectedIssueDate >= GetDate()-30
                     AND I.Status = 'Suggested' AND I.Active = 1;")

#Execute the SQL command
cursor.execute(SQLQuery)


#Fetch all the rows in a list of lists.
results=cursor.fetchall()
y = len(results)
#define function
def Review():
    cursor.close()
    cursor = db1.cursor()
    for result in results: 
        my_OpinionID = result[1] 
        my_StatusID = result[14] 
        cursor.execute('UPDATE [CpamTestAugustTestSteve].[dbo].[NewIssueOpinion] SET Status = ? WHERE OpinionID = ?', (my_StatusID, my_OpinionID))
        db1.commit()
        cursor.close()
        db1.close()    
location.reload()
print "<br> <br>"
print "<body2>"
print "<form method='post' onclick='return Review();'>"
print "<div> <input type='Submit' class= 'submitbutton' value='Submit' /> </div> <br> <br>"
print "</form>"
if  not cursor.rowcount:
    print "<b> <mark> NO RECORDS FOUND!!</mark> </b>"
else:
    print "<TABLE>"
    print "<tablebody>"
    print"<tr>"
    print "<tr><th>S.No</th><th>OpinionID</th> <th>TimeStamp</th> <th>Strategy</th> <th>ExpectedTradingPrice</th> <th>ExpectedDate</th> <th>CPAMAnalyst</th> <th>Conviction</th> <th>Status</th> <th>DebtTicker</th> <th>InstrumentType</th> <th>ExpectedMaturity</th> <th>OrderSize</th> <th>Allocation</th><th>New Status</th>"
    for p in range(y):
        print "<tr><td>%s</td>" %(p+1)
        for q in range(len(results[p])):
            r= results[p][q]   
            print "<td> %s </td>" % (r)
    print "<td><select id='statusSelect'><option value='Suggested'>Select</option><option value='Accepted'>Accept</option><option value='rejected'>Reject</option><option value='terminated'>Terminated</option></select></td>"
    print "</TABLE>"
    from tabulate import tabulate                    
print "</body2>"


db1.commit()

当我单击提交按钮时，页面正在重新加载，但数据库没有更新。不知道出了什么问题！

Answer 1

对于 cursor.execute(SQLQuery, multi=True) 中的结果： if result.with_rows:

同样，上次我尝试连接到数据库并打印我使用的结果

Answer 2

这里有 2 分：

cur.fetchall 返回一个元组的元组。 results[0][0] 将是查询返回的数据中第一行的 OpinionID。 results[1][0] 将是第二行的 OpinionID，以此类推。results [0][7] 将是第一行的 Status，以此类推。

不要使用 Python 的字符串连接构建查询。使用安全的方法。

my_first_OpinionID = results[0][0]
my_first_statusID = results[0][7]  
cur.execute("UPDATE NewIssueOpinion SET Status = ? WHERE OpinonID = ?", (my_first_OpinionID, my_first_statusID))

您可能会发现这些链接很有用：

<http://zetcode.com/db/mysqlpython/>  
<http://bobby-tables.com/python>  
<http://sebastianraschka.com/Articles/2014_sqlite_in_python_tutorial.html>