code: func HashChunkRow(sc *stmtctx.StatementContext, b []byte, row chunk.Row, allTypes []*types.FieldType, colIdx []int) ([]byte, error) {
  	return encodeChunkRow(sc, b, row, allTypes, colIdx, false, true)
  }
docs: // HashChunkRow appends the encoded values to byte slice "b", returning the appended slice.
  // If two rows are equal, it will generate the same bytes.