Method HashValue

pkg/types/json_binary.go:567–616

HashValue converts certain JSON values for aggregate comparisons. For example int64(3) == float64(3.0) Other than the numeric condition, this function has to construct a bidirectional map between hash value and the original representation

(buf []byte)

// Other than the numeric condition, this function has to construct a bidirectional map between hash value
// and the original representation
func (bj BinaryJSON) HashValue(buf []byte) []byte {
	switch bj.TypeCode {
	case JSONTypeCodeInt64:
		// Convert to a FLOAT if no precision is lost.
		// In the future, it will be better to convert to a DECIMAL value instead
		// See: https://github.com/pingcap/tidb/issues/9988

		// A double precision float can have 52-bit in fraction part.
		if getInt64FractionLength(bj.GetInt64()) <= 52 {
			buf = append(buf, JSONTypeCodeFloat64)
			buf = appendBinaryFloat64(buf, float64(bj.GetInt64()))
		} else {
			buf = append(buf, bj.TypeCode)
			buf = append(buf, bj.Value...)
		}
	case JSONTypeCodeUint64:
		// A double precision float can have 52-bit in fraction part.
		if getUint64FractionLength(bj.GetUint64()) <= 52 {
			buf = append(buf, JSONTypeCodeFloat64)
			buf = appendBinaryFloat64(buf, float64(bj.GetUint64()))
		} else {
			buf = append(buf, bj.TypeCode)
			buf = append(buf, bj.Value...)
		}
	case JSONTypeCodeArray:
		// this hash value is bidirectional, because you can get the element one-by-one
		// and you know the end of it, as the elemCount is also appended here
		buf = append(buf, bj.TypeCode)
		elemCount := int(jsonEndian.Uint32(bj.Value))
		buf = append(buf, bj.Value[0:dataSizeOff]...)
		for i := 0; i < elemCount; i++ {
			buf = bj.ArrayGetElem(i).HashValue(buf)
		}
	case JSONTypeCodeObject:
		// this hash value is bidirectional, because you can get the key using the json
		// string format, and get the value accordingly.
		buf = append(buf, bj.TypeCode)
		elemCount := int(jsonEndian.Uint32(bj.Value))
		buf = append(buf, bj.Value[0:dataSizeOff]...)
		for i := 0; i < elemCount; i++ {
			keyJSON := CreateBinaryJSON(string(bj.objectGetKey(i)))
			buf = append(buf, keyJSON.Value...)
			buf = bj.objectGetVal(i).HashValue(buf)
		}
	default:
		buf = append(buf, bj.TypeCode)
		buf = append(buf, bj.Value...)
	}
	return buf
}

// GetValue return the primitive value of the JSON.
func (bj BinaryJSON) GetValue() any {