// Create a Datum representing an integer value intValue := parser.NewDInt(42) // Create a Datum representing a string value stringValue := parser.NewDString("hello world") // Create a Datum representing a null value nullValue := parser.DNull // Check if a Datum represents a null value if nullValue == parser.DNull { fmt.Println("The value is null") } // Convert a Datum representing a decimal value to a float64 decimalValue := parser.NewDDecimal(parser.NewDecFromFloat(3.14)) floatValue, err := decimalValue.Float64() if err == nil { fmt.Println(floatValue) }In the above examples, we create Datum values for integers, strings, and nulls, and also demonstrate how to check if a Datum represents a null value and convert a decimal Datum to a float64. Overall, the Datum type is an integral part of the CockroachDB SQL parser and provides a flexible way to represent SQL values in Go.