1 | /* |
2 | Copyright (c) 2007 Volker Krause <vkrause@kde.org> |
3 | |
4 | This library is free software; you can redistribute it and/or modify it |
5 | under the terms of the GNU Library General Public License as published by |
6 | the Free Software Foundation; either version 2 of the License, or (at your |
7 | option) any later version. |
8 | |
9 | This library is distributed in the hope that it will be useful, but WITHOUT |
10 | ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
11 | FITNESS FOR A PARTICULAR PURPOSE. See the GNU Library General Public |
12 | License for more details. |
13 | |
14 | You should have received a copy of the GNU Library General Public License |
15 | along with this library; see the file COPYING.LIB. If not, write to the |
16 | Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA |
17 | 02110-1301, USA. |
18 | */ |
19 | |
20 | #ifndef AKONADI_QUERY_H |
21 | #define AKONADI_QUERY_H |
22 | |
23 | #include <QtCore/QString> |
24 | #include <QtCore/QVariant> |
25 | #include <QtCore/QVector> |
26 | |
27 | namespace Akonadi { |
28 | namespace Server { |
29 | |
30 | class QueryBuilder; |
31 | |
32 | /** |
33 | Building blocks for SQL queries. |
34 | @see QueryBuilder |
35 | */ |
36 | namespace Query { |
37 | |
38 | /** |
39 | Compare operators to be used in query conditions. |
40 | */ |
41 | enum CompareOperator { |
42 | Equals, |
43 | NotEquals, |
44 | Is, |
45 | IsNot, |
46 | Less, |
47 | LessOrEqual, |
48 | Greater, |
49 | GreaterOrEqual, |
50 | In, |
51 | NotIn, |
52 | Like |
53 | }; |
54 | |
55 | /** |
56 | Logic operations used to combine multiple query conditions. |
57 | */ |
58 | enum LogicOperator { |
59 | And, |
60 | Or |
61 | }; |
62 | |
63 | /** |
64 | Sort orders. |
65 | */ |
66 | enum SortOrder { |
67 | Ascending, |
68 | Descending |
69 | }; |
70 | |
71 | /** |
72 | Represents a WHERE condition tree. |
73 | */ |
74 | class Condition |
75 | { |
76 | friend class Akonadi::Server::QueryBuilder; |
77 | public: |
78 | /** A list of conditions. */ |
79 | typedef QVector<Condition> List; |
80 | |
81 | /** |
82 | Create an empty condition. |
83 | @param op how to combine sub queries. |
84 | */ |
85 | Condition(LogicOperator op = And); |
86 | |
87 | /** |
88 | Add a WHERE condition which compares a column with a given value. |
89 | @param column The column that should be compared. |
90 | @param op The operator used for comparison |
91 | @param value The value @p column is compared to. |
92 | */ |
93 | void addValueCondition(const QString &column, CompareOperator op, const QVariant &value); |
94 | |
95 | /** |
96 | Add a WHERE condition which compares a column with another column. |
97 | @param column The column that should be compared. |
98 | @param op The operator used for comparison. |
99 | @param column2 The column @p column is compared to. |
100 | */ |
101 | void addColumnCondition(const QString &column, CompareOperator op, const QString &column2); |
102 | |
103 | /** |
104 | Add a WHERE condition. Use this method to build hierarchical conditions. |
105 | */ |
106 | void addCondition(const Condition &condition); |
107 | |
108 | /** |
109 | Set how sub-conditions should be combined, default is And. |
110 | */ |
111 | void setSubQueryMode(LogicOperator op); |
112 | |
113 | /** |
114 | Returns if there are sub conditions. |
115 | */ |
116 | bool isEmpty() const; |
117 | |
118 | /** |
119 | Returns the list of sub-conditions. |
120 | */ |
121 | Condition::List subConditions() const; |
122 | |
123 | private: |
124 | Condition::List mSubConditions; |
125 | QString mColumn; |
126 | QString mComparedColumn; |
127 | QVariant mComparedValue; |
128 | CompareOperator mCompareOp; |
129 | LogicOperator mCombineOp; |
130 | |
131 | }; // class Condition |
132 | |
133 | } // namespace Query |
134 | } // namespace Server |
135 | } // namespace Akonadi |
136 | |
137 | Q_DECLARE_TYPEINFO(Akonadi::Server::Query::Condition, Q_MOVABLE_TYPE); |
138 | |
139 | #endif |
140 | |