e.g.)
$ go run main.go readrow "projects/[PROJECT_ID]/instances/[INSTANCE_NAME]/databases/[TABLE_NAME]"
- https://pkg.go.dev/cloud.google.com/go/spanner#section-readme
- https://pkg.go.dev/cloud.google.com/go/spanner#hdr-Single_Reads
- https://github.com/GoogleCloudPlatform/golang-samples/blob/main/functions/spanner/spanner.go
- https://github.com/GoogleCloudPlatform/golang-samples/tree/main/spanner/spanner_snippets
- https://cloud.google.com/spanner/docs/getting-started/go?hl=ja