Question

我为Python 2.7和MariaDB编写了this database class。并且我想在插入成功时打印消息，或者如果元素不存在且插入失败则打印警告。我应该修改数据库类还是它提供的返回值没问题？这是我的尝试：

def  insertProduct (db, name, attrName, attrValue):
    sql = 'INSERT IGNORE `product` SET ' + attrName + ' = %s WHERE `name` = %s'
    sql2 = """SELECT * FROM `product` WHERE `name` = %s"""
    if  db.execute (sql, (attrValue, name))['retval']:
        print "Successfully added ('" + name + "', '" + attrName + "': " + unicode(attrValue) + ") to `product` table"
    elif not  db.execute (sql, (attrValue, name))['retval']:
        print "ERROR: Couldn't add ('" + name + "', '" + attrName + "': " + unicode(attrValue) + ") to `product` table"

Answer 1

if  db.execute (sql, (attrValue, name))['retval']:
        print "Successfully added ('" + name + "', '" + attrName + "': " + unicode(attrValue) + ") to `product` table"
elif not  db.execute (**sql**, (attrValue, name))['retval']:
        print "ERROR: Couldn't add ('" + name + "', '" + attrName + "': " + unicode(attrValue) + ") to `product` table"

在这里，您在中调用db.execute（），如果阻止＆amp;的 elif的即可。假设，如果db.execute（）返回 True ，那么它将打印成功添加的字符串。但db.execute返回 False 然后它将转到 elif 块并再次执行db.execute（），它可以返回 True 或< em> False ，所以如果它是 True ，这意味着插入成功但它不会打印成功消息，但如果是 False 那么它将打印错误：无法添加记录。

if  db.execute (sql, (attrValue, name))['retval']:
        print "Successfully added ('" + name + "', '" + attrName + "': " + unicode(attrValue) + ") to `product` table"
elif not  db.execute (**sql2**, (attrValue, name))['retval']:
        print "ERROR: Couldn't add ('" + name + "', '" + attrName + "': " + unicode(attrValue) + ") to `product` table"

在else块中，它应该是选择查询

如何检查sql insert是否添加了任何内容并选择在python中使用db类获取内容

1 个答案: