The problem has been found because using mongoose.createConnection to connect to the database can only operate the database in the current js. Here I just looked up the data in the users table. In the routing, I also involved data query operations in other tables. There is nothing written there. mongoose.createConnection connection operation library operation.
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Where do the req and res in the error code come from
The problem has been found because using mongoose.createConnection to connect to the database can only operate the database in the current js. Here I just looked up the data in the users table. In the routing, I also involved data query operations in other tables. There is nothing written there. mongoose.createConnection connection operation library operation.