[Memo] MyBatis's mysterious movement, set null to the element of the list object and return it.

For your reference, SQL "Select items are all null" and "return is received as List type", Please note that a nice list object with "size 1" and "list element set to null" will be returned. I don't use it, but I added a line number and avoided it for the time being.

If you check the following contents in advance, it seems that you can avoid the execution bug.

  1. Contains required columns
  2. Contains the column checked for "IS NOT NULL" in the WHERE clause

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