How to get the three tables



  • There are three tables: bookvideoaudiowhich are unconnected. They all have a field. created_at♪ How do I get the data from these three tables and quarry it up? created_at?



  • If the tables match the fields, it makes sense to merge them. If the field tables do not coincide, the three requests and the resulting mass that has already been sorted into the field created_at.




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