Golang编写CSV的新列

I'm writing out two sets of data to one CSV in Go. Right now, using csv.NewWriter, I can write them to the same columns. This is not ideal, I would like them side-by-side, the second dataset in adjacent columns. Here's what I'm doing now:

    csvOut, _ := os.Create("Summary.csv")
    writer := csv.NewWriter(csvOut)

    for _, value := range dataset1 {
            writer.Write(value)
    }
    writer.Flush()
    for _, value := range dataset2 {
            writer.Write(value)
    }
    writer.Flush()

I know the normal writer has some offset options, does the csv writer have anything similar?

Loop over the source data set records. Concatenate the records from each data set to create an output record. Write the output record to the file.

csvOut, _ := os.Create("Summary.csv")
writer := csv.NewWriter(csvOut)

var record []string  // declare record outside loop to reduce allocations
for i := range dataset1 {
        record = append(record[:0], dataset1[i]...) // copy data set 1 to beginning of output record
        record = append(record, dataset2[i]...) // append data set 2 to output record
        writer.Write(record)
}
writer.Flush()

This code assumes that len(dataset1) == len(dataset2). If this is not true, then modify the code per application requirements (add empty values, truncate to shorter dataset, ...)