删除集合中所有文档的查询或其他快速方法是什么？现在我正在删除整个集合并重新创建。
【问题讨论】：
标签： azure azure-cosmosdb
删除集合中所有文档的查询或其他快速方法是什么？
正如 Chris Pietschmann 提到的，Azure 门户目前不支持它，而这个 feature 正在由 Azure Documentdb 团队负责。
我们可以使用服务器端脚本（例如存储过程、udfs、触发器）来做到这一点 我从另一个SO thread 获得以下代码。它在我这边工作正常。
/**
* A DocumentDB stored procedure that bulk deletes documents for a given query.<br/>
* Note: You may need to execute this sproc multiple times (depending whether the sproc is able to delete every document within the execution timeout limit).
*
* @function
* @param {string} query - A query that provides the documents to be deleted (e.g. "SELECT * FROM c WHERE c.founded_year = 2008")
* @returns {Object.<number, boolean>} Returns an object with the two properties:<br/>
* deleted - contains a count of documents deleted<br/>
* continuation - a boolean whether you should execute the sproc again (true if there are more documents to delete; false otherwise).
*/
function bulkDeleteSproc(query) {
var collection = getContext().getCollection();
var collectionLink = collection.getSelfLink();
var response = getContext().getResponse();
var responseBody = {
deleted: 0,
continuation: true
};
// Validate input.
if (!query) throw new Error("The query is undefined or null.");
tryQueryAndDelete();
// Recursively runs the query w/ support for continuation tokens.
// Calls tryDelete(documents) as soon as the query returns documents.
function tryQueryAndDelete(continuation) {
var requestOptions = {continuation: continuation};
var isAccepted = collection.queryDocuments(collectionLink, query, requestOptions, function (err, retrievedDocs, responseOptions) {
if (err) throw err;
if (retrievedDocs.length > 0) {
// Begin deleting documents as soon as documents are returned form the query results.
// tryDelete() resumes querying after deleting; no need to page through continuation tokens.
// - this is to prioritize writes over reads given timeout constraints.
tryDelete(retrievedDocs);
} else if (responseOptions.continuation) {
// Else if the query came back empty, but with a continuation token; repeat the query w/ the token.
tryQueryAndDelete(responseOptions.continuation);
} else {
// Else if there are no more documents and no continuation token - we are finished deleting documents.
responseBody.continuation = false;
response.setBody(responseBody);
}
});
// If we hit execution bounds - return continuation: true.
if (!isAccepted) {
response.setBody(responseBody);
}
}
// Recursively deletes documents passed in as an array argument.
// Attempts to query for more on empty array.
function tryDelete(documents) {
if (documents.length > 0) {
// Delete the first document in the array.
var isAccepted = collection.deleteDocument(documents[0]._self, {}, function (err, responseOptions) {
if (err) throw err;
responseBody.deleted++;
documents.shift();
// Delete the next document in the array.
tryDelete(documents);
});
// If we hit execution bounds - return continuation: true.
if (!isAccepted) {
response.setBody(responseBody);
}
} else {
// If the document array is empty, query for more documents.
tryQueryAndDelete();
}
}
}
在 Azure 门户上执行的更多详细步骤如下：
【讨论】：
在测试环境中，我们发现了将 TTL 设置为 1 秒的技巧，等待 cosmosdb 完成它的工作，然后将 TTL 恢复正常。
很高兴这可以在 azure 门户中完成。
在后台，Cosmosdb 会自行删除所有文档，但确实需要时间。
示例：如果您的集合中有 1000 个文档并且 ttl 已关闭
select count(1) from c = 1000
设置 TTL = 1 秒
select count(1) from c = 0
但是如果您重新打开正常 TTL 并在它有时间删除后台中的所有文档之前进行计数，您会得到与将 TTL 设置为 1 秒之前相同的数字。 在后台将它们全部删除需要时间。
【讨论】：
进行返回 selflink + 分区键（此处= company.id）的查询，然后删除每个文档
protected async Task DeleteAllDocumentsAsync()
{
DocumentClient client = createClient();
//**make query that returns selflink + partition key (here= company.id)**
var docs = client.CreateDocumentQuery("your collection uri", "select c._self, c.company.id from c", new FeedOptions() {EnableCrossPartitionQuery = true}).ToList();
foreach (var doc in docs)
{
var requestOptions = new RequestOptions() {PartitionKey = new PartitionKey(doc.id)};
await client.DeleteDocumentAsync(doc._self, requestOptions);
}
}
【讨论】：
在 Azure 门户中找到了一个 hack。
【讨论】：
目前，您正在执行的方法是通过 Azure 门户执行此操作的唯一方法。您可能希望考虑使用脚本或编码来实现一个工具来为您删除集合，而不是删除集合来完成它。
【讨论】：