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mysqlgogo-gormgo-sqlmock

Go sqlmock test MySQL batch insert

I am using GORM to batch insert multiple rows into a MySQL table and I want to test that the behaviour is the correct one using sqlmock. I haven't found anything online regarding mocking batch inserts with sqlmock.

For inserting a single row, we would have something similar to:

mock.ExpectExec("INSERT INTO product_viewers").WithArgs(2, 3).WillReturnResult(sqlmock.NewResult(1, 1))

But how should multiple rows' values be passed to ExpectExec in order to represent a batch insert?

mock.ExpectExec("INSERT INTO product_viewers").WithArgs(???).WillReturnResult(sqlmock.NewResult(*numInsertedRows*, *numInsertedRows*))
Solution

  • The answer is, at least for MySQL, that sqlmock doesn't make a difference between different rows and columns, so you can just list all the values from all the rows, one after the other, comma separated, in .WithArgs.

    e.g.

    mock.ExpectExec("INSERT INTO product_viewers").
  WithArgs(row1col1, row1col2, row2col1, row2col2, ...).
  WillReturnResult(sqlmock.NewResult(<numInsertedRows>, <numInsertedRows>))