RavenDB中元数据的提取
与SQL Server中类似,我想查询元数据,但在ravenDB中 理想的输出表是RavenDB中元数据的提取,ravendb,Ravendb,与SQL Server中类似,我想查询元数据,但在ravenDB中 理想的输出表是 Column Name | Primary Key | Data Type | Size | Nullability 您可以使用如下查询获取文档的“架构”: declare function Schema(doc) { var fields = []; var keys = Object.keys(doc); for(var i = 0; i < keys.length; i +
Column Name | Primary Key | Data Type | Size | Nullability
您可以使用如下查询获取文档的“架构”:
declare function Schema(doc) {
var fields = [];
var keys = Object.keys(doc);
for(var i = 0; i < keys.length; i ++){
fields.push({
Name: keys[i],
Type: typeof doc[keys[i]]
})
}
return { Fields: fields };
}
from Employees as e
select Schema(e)
limit 1
请注意,在RavenDB中,您并没有真正的模式。不同的单据可能有不同的字段。
根据需求的复杂性,您可能需要递归到嵌套对象中,如
territions
或Address
RavenDB是一个包含json文档的非关系型NoSQL数据库,不涉及任何模式。你的问题到底是什么?
{
"Fields": [
{
"Name": "LastName",
"Type": "string"
},
{
"Name": "FirstName",
"Type": "string"
},
{
"Name": "Title",
"Type": "string"
},
{
"Name": "Address",
"Type": "object"
},
{
"Name": "HiredAt",
"Type": "string"
},
{
"Name": "Birthday",
"Type": "string"
},
{
"Name": "HomePhone",
"Type": "string"
},
{
"Name": "Extension",
"Type": "string"
},
{
"Name": "ReportsTo",
"Type": "string"
},
{
"Name": "Notes",
"Type": "object"
},
{
"Name": "Territories",
"Type": "object"
},
{
"Name": "@metadata",
"Type": "object"
},
{
"Name": "New",
"Type": "string"
}
],
"@metadata": {
"@flags": "HasRevisions, HasAttachments, Reverted",
"@id": "employees/8-A",
"@last-modified": "2019-10-23T15:03:03.0396651Z",
"@change-vector": "A:2239343-ZAAsE6haIECPXQA6XsIt5A, A:1887-0N64iiIdYUKcO+yq1V0cPA, A:6214-xwmnvG1KBkSNXfl7/0yJ1A",
"@projection": true,
"@index-score": 0
}
}