Drizzled Public API Documentation

get_system_var.h
1 /* -*- mode: c++; c-basic-offset: 2; indent-tabs-mode: nil; -*-
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3  *
4  * Copyright (C) 2008 Sun Microsystems, Inc.
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13  * GNU General Public License for more details.
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19 
20 #pragma once
21 
22 #include <drizzled/function/func.h>
23 #include <drizzled/lex_string.h>
24 
25 namespace drizzled {
26 
27 Item* get_system_var(Session*, sql_var_t, str_ref name, str_ref component);
28 
29 /* A system variable */
30 
32 {
33  sys_var *var;
34  sql_var_t var_type;
35  str_ref component;
36 
37 public:
38  Item_func_get_system_var(sys_var *var_arg, sql_var_t var_type_arg, str_ref component_arg, const char *name_arg, size_t name_len_arg);
39  bool fix_fields(Session *session, Item **ref);
40  /*
41  Stubs for pure virtual methods. Should never be called: this
42  item is always substituted with a constant in fix_fields().
43  */
44  double val_real() { assert(0); return 0.0; }
45  int64_t val_int() { assert(0); return 0; }
46  String* val_str(String*) { assert(0); return 0; }
47  void fix_length_and_dec() { assert(0); }
48  /* TODO: fix to support views */
49  const char *func_name() const { return "get_system_var"; }
50 };
51 
52 } /* namespace drizzled */
53