Drizzled Public API Documentation

natural_join_column.h
1 /* -*- mode: c++; c-basic-offset: 2; indent-tabs-mode: nil; -*-
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4  * Copyright (C) 2008 Sun Microsystems, Inc.
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19 
20 #pragma once
21 
22 #include <drizzled/memory/sql_alloc.h>
23 
24 namespace drizzled {
25 
26 /*
27  Column reference of a NATURAL/USING join. Since column references in
28  joins can be both from views and stored tables, may point to either a
29  Field (for tables).
30 */
31 
33 {
34 public:
35  Field *table_field; /* Column reference of table or temp view. */
36  TableList *table_ref; /* Original base table/view reference. */
37  /*
38  True if a common join column of two NATURAL/USING join operands. Notice
39  that when we have a hierarchy of nested NATURAL/USING joins, a column can
40  be common at some level of nesting but it may not be common at higher
41  levels of nesting. Thus this flag may change depending on at which level
42  we are looking at some column.
43  */
44  bool is_common;
45 public:
46  Natural_join_column(Field *field_param, TableList *tab);
47  const char *name();
48  Item *create_item(Session *session);
49  Field *field();
50  const char *table_name();
51  const char *db_name();
52 };
53 
54 } /* namespace drizzled */
55