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This article introduces what to do when spring-data-mongodb uses mongoTemplate to operate MongoDB with @ Indexed annotation is invalid and does not automatically create an index, the content is very detailed, interested friends can refer to, I hope it can be helpful to you.

First put the code, will the following "exception" code automatically create the index?

/ / order doc@Data@Accessors (chain = true) @ FieldNameConstants@Document (collection = "order_") public class Order implements Serializable {@ Id private String id; @ Indexed private String tid; @ Indexed private String tradeId; private String status; private String created;} / / insert using mongoTemplate, according to the monthly table mongoTemplate.insert (orderRecord, mongoTemplate.getCollectionName (Order.class) + month)

The answer is: yes!

So why is the exception code? because it didn't live up to my expectations, this code has two problems:

1. Two collection will be created in mongodb: order_ and order_$ {month}

2. The index will be created in the collection of "order_", not in "order_$ {month}"

At this point, the answer is obvious: when the index is created automatically, the collectionName read is the value in the @ Document annotation, not the value passed in when insert.

Now that we have the conclusion, we should see how it loses the incoming collectionName.

Through debug, you can find the calling path for creating index-related classes and methods:

This is the method signature:

CheckForIndexes ((MongoPersistentEntity) entity)

In the end, all that was left was entity. Get the collectionName through the @ Document annotation of entity. Details will not be mapped, it is recommended to go to debug to see the source code.

The reason has been found, how to solve the current problem in the end? The above code:

/ / Field index IndexOperations indexOps2 = mongoTemplate.indexOps (orderCollectionName); String [] indexFields2 = Arrays.stream (Order.class.getDeclaredFields ()) .filter (f-> f.isAnnotationPresent (Indexed.class)) .map (Field::getName) .toArray (String []:: new) For (String indexField: indexFields2) {if (StringUtils.hasText (indexField)) {indexOps2.ensureIndex (new Index (indexField, Sort.Direction.ASC));}}

At this point, the problem is solved.

Finally, don't forget to remove the @ Document annotation.

The @ Indexed annotation is invalid when spring-data-mongodb uses mongoTemplate to operate MongoDB and what to do without automatically creating an index is shared here. I hope the above content can be helpful to you and you can learn more. If you think the article is good, you can share it for more people to see.

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