如何添加到';地图地图';在DynamoDB中使用boto3(python)
我在DynamoDB中有以下结构:如何添加到';地图地图';在DynamoDB中使用boto3(python),python,amazon-web-services,amazon-dynamodb,boto3,Python,Amazon Web Services,Amazon Dynamodb,Boto3,我在DynamoDB中有以下结构: { "fruits": { "1": { "identifier": "orange", "colour": "orange" }, "2": { "identifier": "strawberry", "colour": "red" } }, "username": "my-username" } 如何添加“第三个水果项目”及其相关属性?我的目标是实现以下目标: {
{
"fruits": {
"1": {
"identifier": "orange",
"colour": "orange"
},
"2": {
"identifier": "strawberry",
"colour": "red"
}
},
"username": "my-username"
}
如何添加“第三个水果项目”及其相关属性?我的目标是实现以下目标:
{
"fruits": {
"1": {
"identifier": "orange",
"colour": "orange"
},
"2": {
"identifier": "strawberry",
"colour": "red"
},
"3": {
"identifier": "pear",
"colour": "green"
}
},
"username": "my-username"
}
result = table.update_item(
Key={
'username': str('my-username')
},
UpdateExpression='set fruits.3.identifier = :i, fruits.3.colour = :c',
ExpressionAttributeValues={
':i': 'pear',
':c': 'green'
}
)
我尝试过类似于以下的方法:
{
"fruits": {
"1": {
"identifier": "orange",
"colour": "orange"
},
"2": {
"identifier": "strawberry",
"colour": "red"
},
"3": {
"identifier": "pear",
"colour": "green"
}
},
"username": "my-username"
}
result = table.update_item(
Key={
'username': str('my-username')
},
UpdateExpression='set fruits.3.identifier = :i, fruits.3.colour = :c',
ExpressionAttributeValues={
':i': 'pear',
':c': 'green'
}
)
谢谢大家! 您不能直接设置属性,例如
水果.3.标识符
,因为水果.3
尚不存在。相反,您必须将fruits.3
设置为一个整体对象
您的更新表达式应该如下所示:
result = table.update_item(
Key={
'username': str('my-username')
},
UpdateExpression='set fruits.3 = :newFruit',
ExpressionAttributeValues={
':newFruit': {
'colour': 'green',
'identifier': 'pear'
}
}
)