java - What is best way to update Google datastore with new fields? -

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I have to add the new table to the existing table, after adding the fields, the application breaks because new records are added to the old records Are not fields and throw exceptions, is there any way to update all old records with newly added areas?

However, according to my expreiences, I am in datastore You have two options for updating a model: You have two options:

  1. Existing rows in the datastore with the default / zero values ​​for newly added columns Update

  2. Add a version based fetch function for pre: To throw an exception in the Cache block, add a new column. A. Use a try catch block, a regular write, which will return the version of the Datastore object 1. Type migration object


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