Drizzled Public API Documentation

hybrid_type.h
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19 
20 #pragma once
21 
22 #include <drizzled/type/decimal.h>
23 
24 namespace drizzled {
25 
26 /*************************************************************************/
27 /*
28  A framework to easily handle different return types for hybrid items
29  (hybrid item is an item whose operand can be of any type, e.g. integer,
30  real, decimal).
31 */
32 
34 {
35 public:
36  int64_t integer;
37 
38  double real;
39  /*
40  Use two decimal buffers interchangeably to speed up += operation
41  which has no native support in decimal library.
42  Hybrid_type+= arg is implemented as dec_buf[1]= dec_buf[0] + arg.
43  The third decimal is used as a handy temporary storage.
44  */
45  type::Decimal dec_buf[3];
46  int used_dec_buf_no;
47 
48  /*
49  Traits moved to a separate class to
50  a) be able to easily change object traits in runtime
51  b) they work as a differentiator for the union above
52  */
53  const Hybrid_type_traits *traits;
54 
55  Hybrid_type() {}
56  /* XXX: add traits->copy() when needed */
57  Hybrid_type(const Hybrid_type &rhs) :traits(rhs.traits) {}
58 };
59 
60 } /* namespace drizzled */
61