1 mike  1.2 //%/////////////////////////////////////////////////////////////////////////////
  2           //

  3 kumpf 1.3 // Copyright (c) 2000, 2001, 2002 BMC Software, Hewlett-Packard Company, IBM,

  4 mike  1.2 // The Open Group, Tivoli Systems
  5           //
  6           // Permission is hereby granted, free of charge, to any person obtaining a copy

  7 kumpf 1.3 // of this software and associated documentation files (the "Software"), to
  8           // deal in the Software without restriction, including without limitation the
  9           // rights to use, copy, modify, merge, publish, distribute, sublicense, and/or

 10 mike  1.2 // sell copies of the Software, and to permit persons to whom the Software is
 11           // furnished to do so, subject to the following conditions:
 12           // 

 13 kumpf 1.3 // THE ABOVE COPYRIGHT NOTICE AND THIS PERMISSION NOTICE SHALL BE INCLUDED IN

 14 mike  1.2 // ALL COPIES OR SUBSTANTIAL PORTIONS OF THE SOFTWARE. THE SOFTWARE IS PROVIDED
 15           // "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT

 16 kumpf 1.3 // LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR
 17           // PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
 18           // HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN

 19 mike  1.2 // ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
 20           // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 21           //
 22           //==============================================================================
 23           //
 24           // Author: Mike Brasher (mbrasher@bmc.com)
 25           //
 26           // Modified By:
 27           //
 28           //%/////////////////////////////////////////////////////////////////////////////
 29           
 30           #ifndef Pegasus_WQLOperation_h
 31           #define Pegasus_WQLOperation_h
 32           
 33           #include <Pegasus/Common/Config.h>
 34           #include <Pegasus/WQL/Linkage.h>
 35           
 36           PEGASUS_NAMESPACE_BEGIN
 37           
 38           /** Represents SQL where clause operators.
 39           
 40 mike  1.2     These operators include the following:
 41           
 42               <ul>
 43           	<li>OR</li>
 44           	<li>AND</li>
 45           	<li>NOT</li>
 46           	<li>=</li>
 47           	<li>&lt;&gt;</li>
 48           	<li>&lt;</li>
 49           	<li>&le;</li>
 50           	<li>&gt;</li>
 51           	<li>&ge;</li>
 52           	<li>IS NULL</li>
 53           	<li>IS NOT NULL</li>
 54           	<li>IS TRUE</li>
 55           	<li>IS NOT TRUE</li>
 56           	<li>IS FALSE</li>
 57           	<li>IS NOT FALSE</li>
 58               </ul>
 59           
 60               Here's an example of a SQL query that uses some of these operations.
 61 mike  1.2 
 62               <pre>
 63           	SELECT *
 64           	FROM MyClass
 65           	WHERE (x &gt; 10 OR y &le; 1.5) OR z = 19 AND name IS NOT NULL
 66               </pre>
 67           
 68               As the parser recognizes these operations, it adds the corresponding
 69               WQLOperation enumeration tag to the WQLSelectStatement by calling
 70               WQLSelectStatement::appendOperation().
 71           
 72               Operators may be converted to string by calling WQLOperationToString().
 73           
 74               Note that in expressions like this one:
 75           
 76               <pre>
 77           	count IS TRUE
 78               </pre>
 79           
 80               The IS operator is NOT treated as a binary operator (which would take
 81               count and TRUE as its operands). Instead, the IS operator and TRUE operand
 82 mike  1.2     are combined to form a single unary operation called "IS_TRUE". In this 
 83               way, evaluation may be implemented by more efficiently (the TRUE operand
 84               is eliminated and therefore need not be handled). Conceptually, the above
 85               expression is equivalent to the following psuedo expression:
 86           
 87               <pre>
 88               	IS_TRUE(count)
 89               </pre>
 90           
 91               Note that this technique is applied the following operations (also 
 92               combined to be unary operations).
 93           
 94               <ul>
 95           	<li>WQL_IS_NULL</li>
 96           	<li>WQL_IS_NOT_NULL</li>
 97           	<li>WQL_IS_TRUE</li>
 98           	<li>WQL_IS_NOT_TRUE</li>
 99           	<li>WQL_IS_FALSE</li>
100           	<li>WQL_IS_NOT_FALSE</li>
101               </ul>
102           */
103 mike  1.2 enum WQLOperation
104           {
105               WQL_OR,
106               WQL_AND,
107               WQL_NOT,
108               WQL_EQ,
109               WQL_NE,
110               WQL_LT,
111               WQL_LE,
112               WQL_GT,
113               WQL_GE,
114               WQL_IS_NULL,
115               WQL_IS_NOT_NULL,
116               WQL_IS_TRUE,
117               WQL_IS_NOT_TRUE,
118               WQL_IS_FALSE,
119               WQL_IS_NOT_FALSE
120           };
121           
122           PEGASUS_WQL_LINKAGE const char* WQLOperationToString(WQLOperation x);
123           
124 mike  1.2 PEGASUS_NAMESPACE_END
125           
126           #endif /* Pegasus_WQLOperation_h */